J Am Acad Audiol 13 : 93-117 (2002)
The Auditory Processing Battery:
Survey of Common Practices
Diana C . Emanuel*
Abstract
A survey of auditory processing (AP) diagnostic practices was mailed to all licensed audiologists
in the State of Maryland and sent as an electronic mail attachment to the American SpeechLanguage-Hearing Association and Educational Audiology Association Internet forums. Common
AP protocols (25 from the Internet, 28 from audiologists in Maryland) included requiring basic audiologic testing, using questionnaires, and administering dichotic listening, monaural low-redundancy
speech, temporal processing, and electrophysiologic tests . Some audiologists also administer binaural interaction, attention, memory, and speech-language/psychological/educational tests and
incorporate a classroom observation . The various AP batteries presently administered appear to
be based on the availability of AP tests with well-documented normative data . Resources for obtaining AP tests are listed .
Key Words : Attention, auditory processing, binaural interaction, central auditory processing,
dichotic listening, memory, monaural low redundancy speech, temporal processing
Abbreviations : ABR = auditory brainstem response ; ACPT = Auditory Continuous Performance
Test ; ADHD = attention-deficit hyperactivity disorder ; AFG = Auditory Figure Ground ; AFT-R =
Auditory Fusion Test-Revised ; ALR = auditory late response ; AMLR = auditory middle latency
response ; AP = auditory processing ; APD = auditory processing disorder ; ARID = acoustic reflex
decay ; ART = acoustic reflex threshold ; ASHA = American Speech-Language-Hearing Association ;
CAP = central auditory processing ; CAPD = central auditory processing disorder ; CHAPS = Children's
Auditory Performance Scale ; CS = Competing Sentences ; CW = Competing Words ; DPT = Duration
Pattern Test; FW = Filtered Words ; MLD = masking level difference ; MLR = middle latency response ;
MMN = mismatched negativity ; OAE = otoacoustic emission ; NU-6 = Northwestern University
Auditory Test No . 6 ; PBKN = Phonetically Balanced Kindergarten in Noise ; PIPB = Performance
Intensity for Phonetically Balanced Words ; PPS = pitch pattern sequence ; PSI = Pediatric Speech
Intelligibility Test ; RASP = Rapidly Alternating Speech Perception ; SCAN = Screening Test for
Auditory Processing Disorders ; SCAN-A = A Test for Auditory Processing Disorders in Adolescents
and Adults ; SCAN-C = Test for Auditory Processing Disorders in Children-Revised ; SIFTER =
Screening Identification for Targeting Educational Risk ; SIN = speech in noise ; SSI-CCM = Synthetic
Sentence Identification with Contralateral Competing Message ; SSI-ICM = Synthetic Sentence
Identification with Ipsilateral Competing Message ; SSW = staggered spondaic word ; TAPS-R =Test
of Auditory Perception Skills ; TTFC = Token Test for Children ; WRS = word recognition score
Sumario
Una encuesta sobre practicas diagn6sticas de procesamiento auditivo (auditory processing : AP)
fue enviada por correo a todos los audi6logos con licencia de ejercicio en el estado de Maryland,
y enviada tambien como archivo de correo electr6nico a la American Speech-Language-Hearing
Association y a los foros de internet de la Asociaci6n de Audiologia Educacional . Los protocolos
de AP recolectados (25 de internet y 20 de audiologos en Maryland) incluyeron elementos en
comun, como evaluaci6n audiol6gica basica, el use de cuestionarios y la administraci6n de pruebas auditivas dic6ticas, lenguaje monoaural de baja redundancia, procesamiento temporal, y
pruebas electrofisiol6gicas . Algunos audiologos tambien administran pruebas de interacci6n binaural, atenci6n, memoria, y pruebas de habla-lenguaje, psicol6gicas y educacionales, e incorporan
una observaci6n en el aula de clase . Las diferentes baterias AP actualmente utilizadas parecen
estar basadas en la disponibilidad de pruebas AP con informaci6n normativa bien documentada .
Se enlistan recursos para obtener [as pruebas AP.
Palabras Clave : Atenci6n, procesamiento auditivo, interacci6n binaural, procesamiento auditivo central, memoria, auditivas dic6ticas, lenguaje monoaural de baja redundancia, procesamiento temporal
*Department of Communication Sciences and Disorders, Towson University, Towson, Maryland
Reprint requests : Diana C . Emanuel, Department of Communication Sciences and Disorders, Towson University, 8000
York Road, Towson, MD 21252-0001
93
Journal of the American Academy of Audiology/Volume 13, Number 2, February 2002
Abreviaturas : ABR = respuestas auditivas de tallo cerebral ; ACPT = Prueba de Ejecuci6n Auditiva
Continua ; ADHD = trastorno de deficiencia atencional con hiperactividad ; AFG = figura fondo
auditiva ; AFTR = Prueba Revisada de Fusion Auditiva ; ALR = respuesta auditiva tardia ;
AMLR = respuesta auditiva de latencia media ; AP = procesamiento auditivo ; APD = trastorno de
procesamiento auditivo ; ARID = fatiga del reflejo acustico estapedial ; ART = umbral del reflejo
acustico estapedial ; ASHA = Asociacion Americana de Habla-Lenguaje-Audicion ; CAP = procesamiento auditivo central ; CHAPS = Escala de Rendimiento Auditivo en Ninos ; CS = Oraciones
en Competencia ; CW = Palabras en Competencia ; DPT = Prueba de Patron de Duracion ; FW = palabras filtradas ; MLD = nivel diferencial de enmascaramiento ; MLR = respuesta de latencia media ;
MMN = negatividad desigual ; OAE = emision otoacustica ; UN-6 = Prueba Auditiva No. 6 de la
Universidad Northwestern ; PBKN = Prueba de Palabras Foneticamente Balanceadas en Ruido
para Ninos Pre-escolares ; PIPB = Prueba de Rendimiento/Intensidad para Palabras Foneticamente
Balanceadas ; PPS = secuencia de patron tonal ; PSI = Prueba de Inteligibilidad de Lenguaje
Pediatrico ; RASP = Prueba de Percepcion de Lenguaje Rapidamente Alternante ; SCAN = Prueba
de Tamizaje para Trastornos de Procesamiento Auditivo ; SCAN-A = Prueba para Trastornos
de
Procesamiento Auditivo en Adolescentes y Adultos ; SCAN-C = Prueba Revisada para Trastornos
de Procesamiento Auditivo en Ninos ; SIFTER= Identificacion por Tam izaje para Encontrar Riesgos
Educacionales ; SIN = lenguaje en ruido ; SSI-CCM = Prueba de Identificacion de Frases Sinteticas
con Mensaje Competitivo Contralateral ; SSI-ICM = Prueba de Identificacion de Frases Sinteticas
con Mensaje Competitivo Ipsilateral ; SSW = palabras espondaicas traslapadas ;TAPS-R = Prueba
Revisada de Habilidad Perceptuales Auditivas ; TTFC = Prueba de TOKEN para Ninos ;
WRS = Puntaje de Reconocimiento de Palabras
he topic of auditory processing (AP),
also called central auditory processing
T (CAP) and central hearing loss, has been
discussed in the professional literature since the
1950s (Mylkebust, 1954) . Within the past
decade, a renewed interest in the topic has
emerged, including an emphasis on defining,
diagnosing, and managing disorders of the central auditory system . In 1995, an American
Speech-Language-Hearing Association (ASHA)
Task Force on central auditory processing disorders (CAPDs) developed a technical report
titled "Central Auditory Processing: Current
Status of Research and Implications for Clinical Practice" (ASHA, 1996) . The task force
defined central auditory processes as
the auditory system mechanisms and
processes responsible for the following
behavioral phenomena : sound localization
and lateralization ; auditory discrimination ;
auditory pattern recognition; temporal
aspects of audition, including-temporal
resolution, temporal masking, temporal
integration, temporal ordering ; auditory
performance decrements with competing
acoustic signals; and auditory performance
decrements with degraded acoustic signals.
CAPD was defined as "an observed deficiency in one or more of the above-listed behaviors ." One recommendation of this task force
was the development of a minimal test battery
94
for assessment of CAPD using physiologic and
behavioral tests.
In October 2000, a consensus statement
was published on the diagnosis of auditory processing disorders (APDs) in school-aged children (Jerger and Musiek, 2000). The consensus
statement included a recommendation to change
the traditional label "central auditory processing disorder" to "auditory processing disorder"
to emphasize the interactions between the
peripheral and central auditory systems . In
addition, the consensus statement recommended
APD screening procedures and a minimum test
battery to differentially diagnose APD in schoolaged children .
The recommended minimum test battery
included pure-tone audiometry, performanceintensity functions for word recognition, a
dichotic task, duration pattern sequence testing,
temporal gap detection, immittance audiometry,
otoacoustic emissions (OAEs), auditory brainstem response (ABR), and middle latency
response (MLR). Optional procedures included
comparing auditory and visual continuous performance measures and conducting cortical
event-related evoked potential testing.
The publication of minimal test batteries for
identifying APD in children is not new (Willeford,
1977 ; Musiek and Chermak, 1994). In 1994,
Musiek and Chermak recommended several
first-order tests, including dichotic digits, competing sentences, frequency patterns, and the
Auditory Processing Battery/Emanuel
Pediatric Speech Intelligibility test (PSI) (Jerger
and Jerger, 1984), and second-order tests, including the MLR, the staggered spondaic word (SSW)
test (Katz, 1962 ; Katz et al, 1963), Tallal's tests
(Tallal and Percy, 1974), and compressed speech
with acoustic modifications, which should be
used in diagnosing APD . Similarly, Bellis and
Ferre (1999) wrote that "a behavioral [AP] test
battery should include at least the following :
dichotic speech tasks, monaural low-redundancy
speech tasks, tests of temporal patterning, and
binaural interaction tasks" (p . 320) . More
recently, Neijenhuis and colleagues (2001) suggested a seven-test AP battery including words
in noise, filtered speech, binaural fusion, sentences in noise, dichotic digits, frequency and
duration patterns, and backward masking in
addition to the use of a questionnaire . Musiek
and colleagues (1982) examined the performance
of children with APD on a battery of tests and
found that four tests-competing sentences, frequency patterns, dichotic digits, and the SSWwere better at detecting auditory perceptual
dysfunction than the Rapidly Alternating Speech
Perception (RASP) test (Ivey, 1969 ; Willeford
1977, 1978), low-pass filtered speech, and binaural fusion .
Individual clinicians often establish sitespecific, or individual-specific, protocols . Oliver
(1987, cited in Chermak et al, 1998) found that
the most commonly reported AP tests for children were the SSW, Willeford Battery (Willeford,
1977) (i.e ., competing speech, filtered speech, binaural fusion, and rapidly alternating speech), and
speech in noise . Chermak and colleagues (1998)
found that the Screening Test for Auditory Processing Disorders (SCAN) (Keith, 1986), acoustic
reflex threshold (ART), and ABR were reported
as the three most frequently used AP procedures . Martin and colleagues (1998) found that
the most commonly reported tests included the
SCAN, speech in noise, SSW, and performanceintensity function for phonetically balanced
words (PIPB) .
The purpose of this study was to investigate
common AP diagnostic practices following the
publication of the APD consensus statement . A
mixed survey (closed- and open-set response format) was developed requesting information on
behavioral and physiologic tests used as part of
the AP battery in addition to the use of checklists,
classroom observation, and tests of memory, attention, and speech-language/psychological/educational ability. The survey was sent via the Internet
to audiologists outside Maryland and mailed to
all audiologists licensed in the State of Mary-
land to determine routine AP assessment practices and conformity with the APD consensus
statement .
METHOD
he survey, titled "Survey of Audiologists'
TCentral Auditory Processing (Auditory Pro-
cessing) Assessment Battery for Children
(Preschool to Age 18)," was posted on the ASHA
(<asha-aud-forum@postman .com>) and Education Audiology Association (EAA) (<eaa-list
@lists .duq .edu>) Internet forums and mailed,
with a postage-paid envelope, to all 352 audiologists licensed by the Maryland State Board of
Examiners . This survey (Appendix A) included
many of the commonly available behavioral AP
tests as well as physiologic tests used to identify AP disorders . The behavioral tests were
grouped into the following categories : monaural
low-redundancy speech, dichotic speech, temporal processing, and binaural interaction (Bellis,
1996 ; Chermak and Musiek, 1997) . Physiologic
tests included the immittance battery, OAE, and
electrophysiologic tests to examine brainstem
and cortical systems . Electrophysiologic tests
included the ABR, auditory middle latency
response (AMLR), auditory late response (ALR),
mismatched negativity (MMN), and P300 . Additional survey questions included the use of
behavioral checklists, physiologic assessment,
auditory attention, classroom observation, auditory memory, speech-language/psychologicaVeducational assessments, and test results from other
professionals via referral or on-site team testing .
The respondents' task was to indicate the
protocol they use to evaluate AP for their pediatric population (preschool to 18 years old) . Each
question consisted of a closed set of response
options and an open-set response item labeled
"other, please specify" because of the large number and diversity of commercially marketed and
research tools that can be used as part of the AP
battery.
The original intention of the study was to survey audiologists only in the author's home state ;
however, posting the survey to the Internet
allowed for comparison of this localized group
with a larger population . Data were not collapsed across the Maryland and Internet groups
because of the different sampling procedures
and diversity of populations . Responses from
the ASHA and EAA Internet forums were collapsed for analysis because the responses were
not always identified by group (ASHA vs EAA),
95
Journal of the American Academy of Audiology/Volume 13, Number 2, February 2002
0
Questionnaire
Monaural Low
d
0
a
N
c
a
U
d
a
20
40
60
80
100
Percent
`
0
20
40
60
80
Dichotic '
Temporal
Binaural Inl
Electrophys
O Internet
Attention
E Maryland
Obsenetion
Memory
Basic Audio .
SLP/P Tests
Other Prof.
Figure l Auditory processing battery reported by audiologists via the Internet (n = 25) and audiologists in the
State of Maryland (n = 28) via regular mail . Monaural
Low = monaural low-redundancy speech ; Dichotic =
dichotic listening; Temporal = temporal processing; Binaural Int = binaural interaction; Electrophys = electrophysiologic tests; Basic Audio. = basic audiologic
assessment ; SLP/P = speech-language/psychoeducational
tests; Other Prof. = other professionals .
and some respondents may have received the
posting on both forums or via forwarded mail
from colleagues .
RESULTS
total of 192 responses (55% response rate)
Awere received from surveys mailed to audiologists licensed in the State of Maryland, and
28 of these (15%) indicated that the respondent
completing the survey conducted AP testing.
Twenty-seven surveys were received in response
to the Internet posting, and 25 responses indicated that the respondent conducted AP testing.
The 25 Internet responses summarized for this
study were received from the following states/
province : Texas (3), Connecticut (1), North Carolina (2), New York (2), Georgia (1), Idaho (1), Colorado (1), Tennessee (1), North Dakota (2),
Louisiana (1), Nebraska (1), Florida (1), Illinois
(1), Ontario (1), and unknown (6).
All respondents who conduct testing indicated that they were certified and/or licensed in
audiology. In addition, eight respondents were
also certified and/or licensed in speech-language
pathology, one was certified in auditory verbal
therapy, and one was certified in deaf education.
General Profile of Test Battery
Figure 1 illustrates responses to survey
questions 3 to 14 for both groups and indicates
that the general profile of the AP test battery was
similar. All of the respondents administer
dichotic speech tests and require a basic audio96
Figure 2 Questionnaires used as part of the auditory
processing battery. CHAPS = Children's Auditory Performance Scale ; Fisher = Fisher Auditory Problems
Checklist; SIFTER = Screening Identification for Targeting Education Risk ; P = preschool.
logic assessment prior to AP testing, and 96
percent administer monaural low-redundancy
speech tests. In addition, over 60 percent of the
respondents from both groups reported the use
of questionnaires, temporal processing tests,
and information from other professional evaluations (via referral or on-site team) as part of the
AP diagnostic protocol . Sixty-four percent of
Internet respondents and 46 percent of Maryland
respondents indicated that electrophysiologic
tests are used in some capacity for AP assessment as part of the standard test battery or as
needed . Fewer than 50 percent from either group
included binaural interaction, attention, classroom observation, memory, and speech-language/psychoeducational tests as part of their
assessment protocol .
The subsequent sections will detail the
results of the survey regarding the individual
components of the AP test battery. These components include the questionnaire ; audiology
evaluation ; behavioral AP test battery; physiologic test battery; and the findings of the survey
regarding assessment of a child's attention,
memory, and speech-language, psychological,
and educational abilities. A list of all of the AP
tests included in the survey, in addition to the
AP and speech-language tests provided by
respondents, is included as Appendix B along
with the current distributors of these tests.
Questionnaire
Most respondents reported that they complete questionnaires as part of the AP battery,
although the Internet group used questionnaires
more frequently than the Maryland group (84%
Internet ; 68% Maryland). Figure 2 illustrates
that the most popular questionnaires were the
Auditory Processing Battery/Emanuel
Percent
Percent
0
20
40
60
80
0
100
PT
SRT
SSI-CCM
DSI
WRS
ci Internet
o, Sentence
Q
40
60
80
DD
SSW
CST
Dichotic CV
Otosc
6
c
20
0Mary land
NS
Plfz
SCAN-C-CW
SCAN-A-CW
SCAN-C-CS
SCAN-A-CS
SCAN-CW
- ]
F
. Internet
0 Maryland
DIRT
Other
Tyrnp
Other
Figure 3 Basic audiologic tests required prior to the
auditory processing battery. Otosc = otoscopy ; PT = puretone testing; SRT = speech recognition threshold ; WRS
= word recognition score; NS = nonsense syllable recognition ; PI fx = performance-intensity function; Tymp =
tympanometry.
Children's Auditory Performance Scale (CHAPS)
(Smoski et al, 1998), Fisher Auditory Problems
Checklist (Fisher, 1976), and the Screening Identification for Targeting Educational Risk
(SIFTER) (Anderson, 1989). Responses in the
"other" category included the Kelly checklists
(Kelly, 1995), Listening Inventory for Education (Anderson and Smaldino, 1996), and checklists developed by individual testing facilities .
Basic Audiologic Evaluation
All of the respondents indicated that basic
audiometric results were required prior to AP
testing . Figure 3 summarizes the most fre-
Percent
0
20
40
60
80
rc
TC+R
Ivey tSIN
PBKN
.
SSI-ICM
SCAN-A_'
SCAN-C-FW
SCAN-C-AFG
SCAN-A-AFG
SCAN FW
SCAN AFG
LPFS
PSI
Other
0lnternet
"Maryland
Figure 4 Monaural low-redundancy (LR) speech tests
used as part of the auditory processing battery. TIC = time
compression; TIC + R = time compression plus reverberation; Ivey = Ivey filtered speech ; SIN = speech in noise;
PBKN = Phonetically Balanced Kindergarten in Noise;
SSI-ICM = Synthetic Sentence Identification with Ipsilateral Competing Message; SCAN-C = Test for Auditory
Processing Disorders in Children-Revised ; FW = Filtered
Words; SCAN-A= Test for Auditory Processing Disorders
in Adolescents and Adults ; AFG =Auditory Figure Ground ;
SCAN = Screening Test for Auditory Processing Disorders;
LPFS = low-pass filtered speech ; PSI = Pediatric Speech
Intelligibility.
Figure 5 Dichotic speech tests used as part of the
auditory processing battery. DD = dichotic digits ; SSW
= Staggered Spondaic Word; CST = Competing Sentence
Test ; CV = consonant vowel; SSI-CCM = Synthetic Sentence Identification with Ipsilateral Competing Message;
DSI = Dichotic Sentence Identification ; SCAN-C = Test
for Auditory Processing Disorders in Children-Revised ;
CW = Competing Words; SCAN-A = Test for Auditory Processing Disorders in Adolescents and Adults ; CS = Competing Sentences ; DRT = Dichotic Rhyme Test .
quently reported components of the basic audiologic battery. All of the respondents required
pure-tone testing and tympanometry. Over 80
percent reported otoscopic examination, word
recognition score (WRS), and speech recognition threshold . Only 24 percent (Internet) and
12 percent (Maryland) of the respondents indicated that a performance-intensity function was
required, and less than 10 percent from either
group reported sentence or nonsense syllable
recognition testing .
Monaural Low-Redundancy Speech Tests
The most commonly reported tests of monaural low-redundancy speech tests for both groups,
illustrated in Figure 4, were the Filtered Word
(FW) and Auditory Figure Ground (AFG) subtests of the Test for Auditory Processing Disorders in Children-Revised (SCAN-C) (Keith, 2000)
and Test for Auditory Processing Disorders in
Adolescents and Adults (SCAN-A) (Keith 1994a) .
The reported use of these tests ranged from 54
to 68 percent. The FW and AFG subtests of the
Screening Test for Auditory Processing Disorders
(SCAN) (Keith, 1986) were reported for 43 percent of the Maryland group but for less than 25
percent of the Internet group. Other reported
tests of monaural low-redundancy speech,
employed less frequently (< 40°/c of the time),
include the Phonetically Balanced Kindergarten
(PBK) test (Haskins, 1949) administered in
noise, low-pass filtered speech test (e .g ., Rintelmann, 1985), Speech in Noise (SIN) test
(Fikret-Pasa, 1993 ; Killion and Villchur, 1993),
97
Journal of the American Academy of Audiology/Volume 13, Number 2, February 2002
0
nN
F
20
Percent
40
60
80
PPS
DPT
Int Pat
d
c Gap Det
A
`o
E
F
AFT-R
plnternet
1m Maryland
PPDT
Other
Figure 6 Temporal processing tests used as part of
the auditory processing battery. PPS = Pitch Pattern
Sequence ; DPT = Duration Pattern Test ; Int Pat = Intensity Pattern Sequence Test; Gap Det = gap detection;
AFT-R = Auditory Fusion Test ; PPDT = psychoacoustic
pattern discrimination test .
time-compressed speech test Northwestern University Auditory Test No . 6 (NU-6), Synthetic
Sentence Identification test with Ipsilateral
Competing Message (SSI-ICM) (Speaks and
Jerger, 1965), PSI, and Ivey filtered speech test
(Ivey, 1969). Approximately 15 percent of the
respondents reported using "other" tests such as
word recognition in various backgrounds, "tests
measuring language processing at a phoneme,
word, sentence and extended discourse level,"
time-compressed PBKs ; "quick" SIN; Hearing in
Noise Test (Nilsson et al, 1994, 1996); and soundfield WRS with +5 and 0 dB signal-to-noise ratio
with four-talker babble .
Dichotic Listening
The results of the survey indicated that the
most commonly reported dichotic tests for both
groups, illustrated in Figure 5, were the SSW
and the Competing Words (CW) and Competing
Sentences (CS) subtests of the SCAN-A and
SCAN-C . The SSW was reported by 76 percent
of Internet respondents and 57 percent of Maryland respondents. The CW and CS subtests of
the SCAN-A were reported by 56 to 64 percent
of respondents . The CW and CS subtests of the
SCAN-C were also frequently reported, with
the Internet respondents more likely to use the
CW (60%) and CS (56%) subtests of this test than
the Maryland group (50% CW 43% CS). The
SCAN (CW only) was reported by 43 percent of
the Maryland group but only 24 percent of the
Internet group (34%). The use of dichotic digit
testing was common for the Internet group (60%)
but much less frequently reported by the Maryland group (18%).
98
Less frequently administered tests of dichotic
listening (< 40%) included the Competing Sentence Test (Willeford, 1978), Synthetic Sentence
Identification Test with Contralateral Competing Message (SSI-CCM) (Speaks and Jerger,
1965), Dichotic Sentence Identification (Fifer et
al, 1983), dichotic consonant vowels (Berlin et al,
1968), and the Dichotic Rhyme Test (Wexler and
Halwes, 1983 ; Musiek et al, 1989). Fewer than
10 percent of the respondents indicated the use
of "other" tests, including the Competing Environmental Sounds test (Katz et al, 1975 ; Arnst
and Katz, 1982) and PSI dichotic sentences .
Temporal Processing
Temporal processing involves the perception
of a sequence of acoustic events . The consensus
statement has recommended that temporal processing be evaluated both in terms of temporal
ordering/sequencing (frequency pattern, duration pattern) and gap detection abilities.
The most commonly reported test of temporal ordering, illustrated in Figure 6, was the
Pitch Pattern Sequence Test (PPS) (Pinheiro,
1977), which was reported by 76 percent of the
Internet respondents and 61 percent of the
Maryland respondents . The Duration Pattern
Test (DPT) (Musiek et al, 1990) was also commonly part of the AP battery for Internet respondents (44%) but was less frequently used by the
Maryland group (11%).
The most frequently reported test of gap
detection in the current study was the Auditory
Fusion Test-Revised (AFT-R) (McCrosky and
Keith, 1996) . It is almost exclusively employed
by a small group of Internet respondents (28%),
with very few reported from the Maryland group
(4%) . Less than 20 percent of the respondents
reported conducting any other listed test . "Other"
reported tests in this category included the
Screening Test for Auditory Perception (Kimmell
and Wahl, 1970).
Binaural Interaction
Figure 7 illustrates that Internet respondents were almost twice as likely to include binaural interaction tests in their battery than
Maryland respondents. The RASP (Ivey, 1969 ;
Willford, 1977, 1978) and masking level difference (MLD) (e .g., Hirsh, 1948 ; Licklider 1948)
were the most commonly reported tests of binaural interaction by Internet respondents; however, these tests were reported less than 25
percent of the time . Less frequently listed tests
Auditory Processing Battery/Emanuel
Percent
Percent
0
5
10
15
20
25
0
30
10
20
30
40
50
ACPT
m Conners
N
d
pInternet
pInternet
EMary land
0Maryland
I
Figure 7 Binaural interaction tests used as part of
the auditory processing battery. RASP = Rapidly Alternating Speech Perception; BF = binaural fusion ; MLD =
masking level difference ; NU-6 = Northwestern University Auditory Test No . 6; CVC Fus = consonant-vowel-consonant fusion ; Loc/Lat = localization/] ateralization.
Attention tests used as part of the auditory
processing battery. ACPT = Auditory Continuous Performance Test ; Conners = Conners' Continuous Performance Test ; Vigil = Vigil Continuous Performance Test ;
SAAT = Selective Auditory Attention Test.
Figure 9
Physiologic Tests
included binaural fusion (Ivey, 1969 ; Willeford
1977, 1978), segmented-alternated consonantvowel-consonant fusion (Wilson et al, 1984, Wilson, 1994), and binaural fusion (band-passed)
NU-6 (Wilson and Mueller, 1984) . The respondents were also asked to indicate if they assess
the localization and lateralization abilities of
their subjects . Twelve percent of the Internet
group and 14 percent of the Maryland group
indicated that they assess localization and lateralization abilities, but only four respondents
indicated how the test was performed . These four
respondents indicated that they asked the
patient to point to the speaker from which a
signal was heard . In addition, one of these
respondents indicated that she asked the parents about the child's localization ability.
ABR
OAE
ART
ARD
plnternet std
AMLR
EInternet ext
MMN
P300
[]Maryland std
r-
;~ Maryland ext
Y I"
Other
Figure 8 Physiologic tests used as part of the standard
(std) or extended (ext) auditory processing battery. ABR
= auditory brainstem response ; CIAE = otoacoustic emission ; ART = acoustic reflex threshold ; ARD = acoustic
reflex decay; AMLR = auditory middle latency response ;
ALR = auditory late response ; MMN = mismatched negativity ; P300 = P300 auditory evoked response potential;
I = immittance audiometry.
Figure 8 illustrates that the most common
physiologic test administered as part of the standard AP battery was immittance (79% Maryland,
92% Internet), with 71 percent (Maryland) and
76 percent (Internet) reporting the ART test,
specifically, as part of the standard battery. Less
than 40 percent of respondents indicated that
they conduct acoustic reflex decay (ARD) testing . Less than 50 percent of respondents reported
including OAEs as part of the standard AP battery (46% Maryland, 44% Internet), but most
Internet respondents included OAEs as part of
either their standard or their extended test battery. "Other" responses from the survey included
the use of ipsilateral and contralateral suppression of OAEs as part of the AP battery.
Percent
ALR
The consensus statement recommended a
minimal AP test battery that included both
behavioral and physiologic assessments designed
to target both the peripheral and central auditory systems .
Electrophysiologic tests were reported as
part of the standard AP battery for less than 15
percent of respondents ; however, many of the
electrophysiologic tests were reported as part of
the extended test battery. The ABR was the
most frequently reported electrophysiologic test,
with 64 percent (Internet) and 46 percent (Maryland) reporting that ABR was part of either the
standard or the extended test battery. AMLR was
rarely part of the standard test battery (4%
Internet, 7% Maryland) but was more frequently
included as part of the extended test battery
(36% Internet, 18% Maryland), especially for
Internet respondents. Fewer than 35 percent
of respondents included any cortical eventrelated potentials (ALR, MMN, P300), even in
99
Journal of the American Academy of Audiology/Volume 13, Number 2, February 2002
Percent
0
5
10
15
Percent
20
25
0
TAPS
13
GFW
m
Z DAPST
E
d
M
N
d
1 [1 Internet
E Maryland
AMST
Other
Figure 10 Memory tests used as part of the auditory
processing battery. TAPS = Test of Auditory Perceptual
Skills ; GFW = Goldman-Fristoe-Woodcock Auditory Memory Test ; DAPST = Denver Auditory Phoneme Sequencing Test ; AMST = Auditory Sequential Memory Test.
the extended test battery, with the Internet
respondents much more likely to conduct these
tests than the Maryland group.
Auditory Attention
Based on this survey, 40 percent of Internet
and 32 percent of Maryland respondents conduct
an attention assessment. Examination of Figure
9 indicates that the most commonly reported
attention assessment for both groups was the
Auditory Continuous Performance Test (ACPT)
by Keith (1994b) . This test was reported for 40
percent of the Internet group and 18 percent of
the Maryland group.
Other tests of attention reported less than
15 percent of the time include the Conners' Continuous Performance Test (Conners, 1994), Vigil
Continuous Performance Test (Vigil, 1996), and
Selective Auditory Attention Test (Cherry, 1980).
One "other" response included "a test of Executive Function to rule out [attention-deficit hyperactivity disorder] ADHD ." Executive function
is "a component of metacognition that refers to
a set of general control processes that ensure that
an individual's behavior is adaptive, consistent
with some goal and beneficial to the individual"(Chermak and Musiek, 1997, p. 16-17) .
However, the respondent did not include a
description of the procedures used to assess
executive function .
Classroom Observation
Less than one-third of the respondents indicated that they routinely performed a classroom
observation/assessment . Reported observation
protocol included site-specific checklists ; observations by a teacher, social worker, or counselor;
100
TALC-3
a
Flowers
H
10
15
20
25
30
TAPS
GFW
LAC
ADT
~
O
w
T
5
Token
Ip Internet
0Maryland '
Woodcock
CELF-3
Phon Aware
Other
Figure 11 Speech-language/psychoeducational tests
used as part of the auditory processing battery. TAPS =
Test ofAuditory Perceptual Skills ; GFW = Goldman-Fristoe-Woodcock Auditory Memory Test ; LAC = Lindamood
Auditory Conceptualization; ADT = Auditory Discrimination Test ; TACL-3 = Test for Auditory Comprehension
of Language-3 ; Token = Token Test for Children ; Flowers
Flowers-Costello Test of Central Auditory Abilities;
Woodcock = Woodcock-Johnson Psychoeducational BatteryRevised; CELF-3 = Clinical Evaluation of Language Fundamentals; Phon Aware = phonologic awareness.
and forms from the Educational Audiology Handbook by DeConde Johnson and colleagues (2001) .
Memory
Auditory memory was assessed by just over
20 percent of each group. Figure 10 indicates that
the most commonly reported test for auditory
memory was the Test of Auditory Perceptual
Skills (TAPS-R) (Gardner, 1997), with 21 percent
of Maryland respondents and 16 percent of Internet respondents listing this test . Less than 5 percent of respondents reported using the Denver
Auditory Phoneme Sequencing Test (DAPST)
(Aten, 1979). "Other" reported tests for assessing memory included the Token Test for Children
(TTFC) (DiSimoni, 1978), Detroit Test of Learning Aptitude (Hammill, 1998), "memory for sentences from several sources," and "digit span"
(presumably, the Visual Aural Digit Span test by
Koppitz, 1975).
Speech-Language and
Psychoeducational Testing
Thirty-two percent (Internet) and 19 percent
(Maryland) of the respondents reported incorporating speech-language/psychoeducational
tests as part of their assessment protocol . Of the
respondents conducting speech-language/psychoeducational tests, 50 percent (Internet) and
20 percent (Maryland) were dually certified in
audiology and speech-language pathology. Figure 11 illustrates that the tests reported most
frequently by the Internet group included the
Auditory Processing Battery/Emanuel
Percent
0
20
40
60
80
Psyc
Educat
SLP
Otolaryn
0 Internet std
W Internet ext
pMaryland std
0Maryland ext
Neurol
Other
Figure 12
Other professional evaluations used as part
of the standard (std) or extended (ext) auditory processing battery. Psych = psychologist ; Educat = educational
assessment ; SLP = speech-language pathologist ; Otolaryn = otolaryngologist ; Neurol = neurologist .
Lindamood Auditory Conceptualization Test
(Lindamood and Lindamood, 1979), by 28 percent of Internet respondents, and the Clinical
Evaluation of Language Fundamentals (Semel
et al, 1995), by 20 percent of Internet respondents. Maryland respondents most frequently
reported the TAPS (18%), which was also
reported by 16 percent of the Internet group .
Other tests reported by less than 20 percent of
respondents included the TTFC, Phonological
Awareness Test (Robertson and Salter, 1997),
Woodcock-Johnson Psychoeducational BatteryRevised (Woodcock and Johnson, 1989), Test for
Auditory Comprehension of Language-3 (Carrow-Woolfolk, 1999b), and Auditory Discrimination Test (Reynolds, 1994). "Other" reported
tests included the Comprehensive Test of Phonological Processing (Wagner et al, 1999), Photo
Articulation Test (Lippke et al, 1997), Peabody
Picture Vocabulary Test-Revised (Dunn and
Dunn, 1981), Expressive One-Word Picture
Vocabulary Test (Brownell, 1990), Test of PhonologicalAwareness (Torgesen and Bryant, 1994),
Phono-Graphic pretest (McGuinness et al, 1996),
Oral and Written Language Scales (CarrowWoolfolk, 1996), Comprehensive Assessment of
Spoken Language (Carrow-Woolfolk, 1999a),
Slosson Oral Reading Test (Nicholson, 1990),
Gray Oral Reading Test (Wiederholt and Bryant,
2001), Test of Word Finding (German, 1991),
and the Test of Written Language (Hammill and
Larson, 1996).
Other Professional Evaluations as Part
of the AP Protocol
Figure 12 indicates that the most common
referral/team assessments reported as part of the
standard AP protocol or extended battery were
a speech-language evaluation (92% Internet,
75% Maryland), an educational evaluation (76%
Internet, 72% Maryland), and a psychological
evaluation (76% Internet, 72% Maryland) .
Approximately 40 percent of both groups also
reported an educational and psychological assessment as part of the standard protocol for AP
assessment . Evaluation by other professionals
(otolaryngologist, neurologist) was rarely
reported as part of the standard battery but
was reported on an "as needed" basis by more
than 50 percent of respondents . "Other"
responses included assessments by a counselor,
developmental pediatrician, and neuropsychologist and input from a parent interview.
Test Battery
Each survey was examined to determine if
the individual respondent followed the minimum behavioral and physiologic test battery
suggested by the APD consensus statement .
Specifically, each response was examined to
determine if the respondent included pure-tone
audiometry, a performance-intensity function, a
dichotic task, duration pattern sequence testing,
temporal gap detection (either "gap detection"
generically or the AFT), immittance audiometry,
OAEs, ABR, and AMLR tests .
None of the respondents listed all of the
tests suggested by the APD consensus statement
minimum test protocol . All of the respondents
reported using dichotic tests, pure-tone audiometry, and some portion of the immittance battery,
and over 60 percent of the respondents reported
temporal processing tests; however, less than
50 percent reported conducting a DPT or a gap
detection test, with the Internet group more
likely to conduct these tests. Only 24 percent
(Internet) and 12 percent (Maryland) of the
respondents indicated that a performance-intensity function was required . In addition, less than
30 percent of respondents indicated that they
administered the SSI-ICM or PSI, two tests that
can be administered in a performance-intensity
format for synthetic sentences (SSI-ICM), meaningful sentences (PSI), or words (PSI).
DISCUSSION
Questionnaire
Questionnaires are given to parents, care
givers, and teachers to assess observed behaviors and competencies in children suspected of
APD . The CHAPS, the Fisher, and the SIFTER
101
Journal of the American Academy of Audiology/Volume 13, Number 2, February 2002
provide information regarding the specific type
of functional difficulties the child is experiencing . In addition, responses can be tallied to
indicate if the child is below normal or at risk
academically. Most of the respondents from
both the Internet and Maryland groups
reported using questionnaires as part of the AP
battery.
The most commonly reported questionnaire,
the CHAPS, was created to "systematically collect and quantify the observed listening behaviors of children . . . [and] can be useful in
prescribing therapeutic intervention and/or the
need for classroom accommodations" by having
an observer (such as the child's teacher) answer
questions across six conditions, including quiet,
ideal, multiple inputs, noise, auditory memory/sequencing, and auditory attention span
(Smoski et al, 1998) . The CHAPS manual
includes the results of a study of 64 children with
APD (Smoski et al, 1992), test-retest reliability
data for 20 of these children, and normative
data based on 20 non-APD children of similar age
and background. Areported case study using the
CHAPS (Garstecki et al, 1990) showed an
improvement in CHAPS score and in CAP diagnostic tests following auditory processing therapy, suggesting that the CHAPS may be a useful
tool as part of the diagnosis and management
protocol for children with APD.
The SIFTER, the second most commonly
reported test from the current study, is broken
down into five categories : academics, attention,
communication, class participation, and school
behavior. Normative data provided with the
SIFTER include a much larger sample size (530
impaired, 50 typical). Although it was the second most commonly reported test in the current study, a limitation of this test is that it
was designed for and tested on children with
peripheral hearing loss rather than APD (Anderson, 1989 ; Dancer, 1995 ; Wray et al, 1997).
The Fisher includes a broad range of general items such as "has a history of hearing loss"
and "has difficulty with phonics" ; however, the
items are not classified into specific categories,
which makes it somewhat more limited for use
in the AP battery than the CHAPS and SIFTER .
Basic Audiologic Evaluation
The current study indicated that 100 percent
of respondents required a pure-tone test and
tympanometry and close to 100 percent required
a WRS prior to AP testing; however, less than 25
percent were conducting performance-intensity
102
functions . This is consistent with trends in audiologic testing reported by Martin et al (1998), who
found that PIPB testing decreased significantly
from approximately 72 percent (1989) to 44 percent (1992) to 26 percent (1997) . However, in
the Martin et al study, PIPB was presumably
used for retrocochlear diagnosis rather than for
AP assessment . Performance-intensity functions
in the AP battery can also be useful for examining word recognition performance between ears,
across presentation level, and with various stimuli for children .
AP is generally assessed in children with
normal peripheral hearing sensitivity. According
to ASHA (1996), there is little systematic research
on the effect of peripheral hearing loss on AP
tests, and few tests are available to separate the
effects of central versus peripheral pathology.
ASHA (1996) suggested that AP testing could be
administered with a peripheral hearing loss if the
results are viewed with caution, tests are selected
that are minimally impacted by peripheral hearing loss (such as dichotic digits, CS, MLR, and
P300), and the effects of the peripheral hearing
loss are taken into account in the interpretation
of the AP tests. The importance of assessing
peripheral hearing sensitivity was also emphasized by the APD consensus statement, which
suggested that a minimal test battery include
pure-tone audiometry, performance-intensity
functions for word recognition, and immittance
audiometry. With the exception of performanceintensity functions, respondents from the current
study were following suggested guidelines for
assessing peripheral hearing sensitivity prior to
AP assessment .
Monaural Low-Redundancy Speech Tests
Monaural low-redundancy speech tests
deliver auditory stimuli, to one ear at a time, that
have been altered with techniques such as filtering, time compression, and background noise
to reduce the inherent redundancy in the speech
signal to make it more difficult for a disordered
central auditory nervous system to decode the
signal .
The most popular tests in this category were
the FW and AFG subtests of the SCAN, SCANA, and SCAN-C . Although other subtests (CW
CS) are listed under the dichotic portion of this
article, the general test will be described here .
The SCAN was originally marketed as an AP
screening battery that could be administered
via standard cassette player in a quiet room or
via clinical audiometer in a sound booth; how-
Auditory Processing Battery/Emanuel
ever, Emerson et al (1997) found that SCAN
scores obtained in a quiet school setting were
markedly different from scores obtained in a
sound booth . The SCAN has been criticized as
an AP assessment tool because of the absence of
a temporal processing measure (Bellis, 1996),
limited normative data sample for 3 to 4 year olds
(Chermak and Musiek, 1997), and questionable
reliability (Amos and Humes, 1998) .
The SCAN-A was developed to extend this
battery ofAP tests to adolescents and to adults .
In addition to the three-subtest format used in
the SCAN (FW AFG, and CW), it includes a
fourth subtest of CS . The word "screening" does
not appear in the title of the SCAN-A . It is simply "A Test for Auditory Processing Disorders in
Adolescents and Adults ."
The SCAN-C is a revision of the SCAN and
is designed for children 5 years of age to 11 years,
11 months of age . Significant changes from the
original SCAN include the use of the four-subtest format (FW AFG, CW CS) similar to the
SCAN-A ; a change in the title, omitting the term
"screening" and calling the instrument "Test for
Auditory Processing Disorders in ChildrenRevised" ; providing the test on compact disc
rather than cassette ; improving the test instructions to the child ; and eliminating normative
data for 3- and 4-year-old children .
The use of the SCAN-C, SCAN-A, and SCAN
as part of a diagnostic battery remains the subject of debate, with some asserting that it is a
screening test (Medwetsky, 1994 ; Hall, 1999)
and clinicians relying on it as part of their test
battery based on findings from the current study
and the results of the Martin et al (1998) and
Chermak et al (1998) studies .
Dichotic Listening
Dichotic listening tasks involve presenting two different stimuli, one to each ear, simultaneously. The listener is required to repeat or
identify stimuli from one or both ears . The
SSW, SCAN-C, and SCAN-A (CW and CS subtests) were three of the most popular tests
according to this survey. An advantage to using
the SSW for assessment of AP is that studies
of the SSW are prevalent in the professional lit-
erature for children (Myrick, 1965 ; Stubblefield and Young, 1975 ; White, 1977 ; Johnson
and Sherman, 1979 ; Johnson et al, 1981 ;
Berrick et al, 1984 ; Windham, 1985 ; Windham
et al, 1986) and adults (Katz et al, 1963 ; Arnst
and Katz, 1982) . Similarly, the SCAN-C and
SCAN-A provide detailed information regard-
ing administration and interpretation for adults
and children and are prevalent in the literature
(Keith, 1994a, 2000).
Dichotic digits (Musiek, 1983) were also frequently reported by the Internet group but rarely
by the Maryland group . Dichotic digits tests are
easy to obtain but come with sparse documentation for test administration and interpretation .
Reports of performance on dichotic digit tests for
adults and children are available in the literature (Musiek and Geurkink, 1980 ; Musiek, 1983 ;
Musiek and Pinheiro, 1985 ; Musiek et al, 1991 ;
Jirsa, 2001) . Clinicians should be aware that normative data available in the professional literature may be specific to a particular recording
and that clinicians should collect their own normative data (Musiek, personal communication,
July 17, 2001) .
Temporal Processing
The consensus statement stressed the
importance of temporal processing tests by recommending that the minimal battery include
three tests specifically designed to target temporal processing : duration patterns, frequency
patterns, and gap detection. More than 60 percent of all respondents indicated that they conduct frequency pattern tests, but few indicated
the use of a duration pattern test or a test of gap
detection.
Research in auditory perception has indicated some basic characteristics of temporal
processing ability in humans, including the following : sounds separated by an interval less
than 2 msec are perceptually fused by the listener ; as the interval between sounds increases
beyond about 2 msec, a listener can identify the
presence of the interval, and this interval has to
be 15 to 20 msec for a listener to accurately
report which of the sounds occurred first (Hirsh,
1959) . Accuracy of detecting order of presentation is crucial in speech discrimination . A linguistic example of the importance of accuracy in
ordering of information includes perceiving the
"t" prior to the "s" for accurate perception of the
word "fits" rather than the word "fist." Hirsh
(1959) asserted that the large temporal interval
required for accurate identification of temporal
order suggested that anatomic and physiologic
systems beyond the peripheral auditory system
must be involved in judgment of these acoustic
events . Every central auditory nucleus within the
central nervous system up to and including the
auditory cortex has been found to be sensitive
to the effects of time (Pinheiro and Musiek,
103
Journal of the American Academy of Audiology/ Volume 13, Number 2, February 2002
1985). The ability of humans to speak and understand language is dependent on the sensitivity
of the central auditory nervous system to process
sound sequences, and difficulty with temporal
processing of auditory signals has been associated with language impairment (Tallal 1980 ;
Tallal et al, 1993 ; Phillips, 1999 ; Chestnik and
Jerger, 2000).
Temporal ordering/sequencing tests involve
a behavioral ordering (e .g., verbal labeling, humming) of acoustic stimuli (e .g ., noise, tones,
clicks, speech) that vary in intensity, frequency,
and/or duration (Pinheiro and Musiek, 1985).
Commercially available tests include both frequency pattern and duration pattern sequences.
Although both frequency and duration pattern
sequence tests yield bilateral deficits in response
to unilateral central lesions, performance for
these two tests has been shown to differ
markedly for subjects with central lesions and
therefore appears to involve different auditory
processes (Musiek et al, 1990).
Frequency pattern tests were reported more
than any other temporal processing test. These
tests are commercially available from three
sources : Auditec, Audiology Illustrated, and the
Veterans' Administration . The PPS test, available from Auditec, has child (6-9 years) and
adult (age 9 to adult) versions, with identical
scoring sheets . The listener is required to hum
or verbally label tones from a three-tone series
as "low" or "high." The children's version by
Auditec includes increased tone duration, interburst interval, and interpattern interval compared with the adult version. The scoring
information provided with the Auditec child version includes means and ranges for children in
three age categories with no other references or
other normative data. The adult version from
Auditec includes means and ranges for 9 to 10
year olds and for adults with no additional normative data or references . The Audiology Illustrated version (Frequency Pattern Test) includes
a one-page instruction sheet listing normal
scores for each year from 8 to 11 and 12 to adult
norms. In addition, two references are included
(Musiek and Pinheiro, 1987 ; Musiek, 1994). The
Veterans' Administration (1992) DPT is not
accompanied by supporting literature . Normative data can be found in the literature for adults
(Musiek, 1994).
The Audiology Illustrated frequency pattern test instructions, unlike the Auditec test
instructions, do not include reversals (e .g., low
high low for high low high) as normal . Musiek
(1994) pointed out that although a certain num104
ber of reversals are seen for normal-hearing
subjects, subjects with brain abnormalities have
a large number of reversals, and they should be
considered incorrect for frequency pattern tests .
Normative data for these tests do not separate
"hummed" and "verbal" response norms . This
may be useful information for test distributors
to provide considering the different performances
seen for children with APD for hummed versus
verbal response (Jirsa, 2001) . Musiek and colleagues (1980) found that split-brain patients
could not accurately report a frequency pattern
verbally; however, hummed responses were normal or near normal for the subjects they studied. They suggested that these findings indicate
that both hemispheres and the corpus callosum
were required to decode a frequency pattern
and report the results verbally, presumably the
right for decoding spectral content and the left
for speech-language and temporal ordering .
DPTs are also available from Audiology
Illustrated, Auditec, and the Veterans' Administration. This test requires the listener to identify each element in a three-tone series as "long"
or "short ." The Audiology Illustrated version
comes with one page of instructions and background information. Specifically, it states that
70 percent and above is normal for adults, and
there are no child normative values . References
are included (Musiek et al, 1990 ; Musiek, 1994),
and it is recommended that clinicians establish
their own normative values . The Duration Pattern Sequence Test (Auditec) comes with a onepage instruction sheet and states that scores
below 67 percent should be considered abnormal.
One reference is provided (Musiek et al, 1990),
and the age range for this test is not given. Normative data for adults on the Veterans' Administration DPT are available from Musiek (1994) .
Additional information regarding frequency
and DPTs is available in the literature for children and adults (e .g ., Pinheiro and Ptacek, 1971 ;
Ptacek and Pinheiro, 1971 ; Musiek and
Geurkink, 1980 ; Pinheiro and Musiek, 1985 ;
Musiek and Pinheiro, 1987 ; Phillips, 1999; Jirsa,
2001). At present, further study of duration pattern testing in children is needed.
Gap detection tests were reported infrequently in the current study. A gap detection
task involves identifying the presence of a brief
silent period between two bursts of sound. Listeners may be required to identify which of
two sounds contains a gap or to indicate if a gap
was present in a single stimulus . The smallest
discernible silent period is called the gap detection threshold. Gap detection threshold varies
Auditory Processing Battery/Emanuel
based on test paradigm, with the lowest gap
detection thresholds associated with broadband signals . High-frequency narrow-band signals yield lower gap detection thresholds than
low-frequency narrow-band signals, and within-
channel paradigms are associated with smaller
gap detection thresholds than between-channel
designs (Phillips, 1999) . According to Jerger
and Musiek (2000), the recommended gap detection test is one in which a "short silent gap is
inserted in a burst of broad-band noise ." This
type of test, however, is not commercially avail-
able at present (Musiek, personal communication, July 17, 2001) .
Of the less than 30 percent of respondents
who indicated that they conduct gap detection
testing, the most frequently reported test was
the AFT-R . The AFT-R does not meet the exact
description of a gap detection test specified by
Jerger and Musiek (2000) ; however, it requires
listeners to identify the presence of a silent gap
(interpulse interval) occurring between two tone
pulses and thus would fall into the general category of gap detection tasks . The listener must
identify if he/she hears one tone or two in a
series of ascending and descending interpulse
interval trials . An advantage of this test is that
it is commercially available and can be administered to adults and children as young as 3
years, assuming that the listener understands
the difference between "one" and "two ." A disadvantage of this test is the testing paradigm,
which includes predictable ascending and
descending interpulse interval trials of 0 to 40
msec (40-300 msec for the expanded test) . A
modification of the AFT-R, the Random Gap
Detection Test, was recently developed by Keith .
This modification uses random interpulse intervals rather than a series of ascending and
descending interpulse interval trials .
Binaural Interaction
Specific tests of binaural interaction, including tests that require a listener to combine separate but simultaneously presented information
to each ear (binaural fusion, RASP) and tests
that determine auditory threshold for binaurally presented stimuli in background noise
before and after the phase shift of the stimulus
or noise (MLD), were reported by less than 25
percent of respondents. In addition, localization
and lateralization tests were infrequently
reported in the current study. This is not surprising, considering that commercially available tests of localization/lateralization are not
available at this time . However, there are published methodologies for testing (Cranford et
al, 1990 ; Besing and Koehnke, 1995; Abouchacra
et al, 1998), and a virtual localization test that
can be administered via compact disc, currently
still in laboratory trials, may be released for
clinical use shortly (Besing, personal communication, July 24, 2001).
Physiologic Tests
Many of the respondents indicated that they
include ART tests as part of their AP battery. Presumably, audiologists are attempting to eliminate the possibility of peripheral, cranial nerve
VIII, or low brainstem pathology as a cause of
AP difficulties prior to examination of more central involvement. This test can be useful for AP
testing, as shown by a case study reported by
Lenhardt (1981) of a child with APD caused by
a low brainstem dysfunction that was investigated only because of absent acoustic reflexes
during an audiologic examination.
Few respondents indicated that they conduct
ARD testing. This is not surprising, considering
the limited additional value of ARD testing for
AP diagnosis compared with the possibility of
inducing tinnitus and hearing threshold shift
with high-intensity stimuli during this test
(Hunter et al, 1999).
OAE testing was reported by just over 40
percent of the respondents from each group as
part of the standard battery but by almost 80 percent of the Internet group as part of the standard
or extended battery. OAEs are specified by the
consensus statement as "useful in ruling out
inner ear disorders" (p . 471) . Presumably, OAEs
as part of the AP battery are used to' further
investigate the peripheral auditory system
including comparison of OAE results with ABR
results to rule out auditory neuropathy (Hood,
1998). Surprisingly, only one respondent indicated the use of an OAE suppression test using
ipsilateral and contralateral noise . This test has
been shown to identify problems with the efferent auditory system (Hall, 2000).
Although less than 15 percent of respondents indicated using the ABR as part of their
standard AP test battery, 64 percent (Internet)
and 46 percent (Maryland) reported using it as
part of either their standard or their extended
test battery. These results are similar to the
findings of Chermak et al (1998), who found 59
percent of respondents administered ABR with
a rating from 4 to 6 (0 = never, 1= least, 6 = most
used), with only a few respondents reporting
105
Journal of the American Academy of Audiology/ Volume 13, Number 2, February 2002
the use of any other electrophysiologic test (MLR
and P300). Later evoked potentials were reported
infrequently in the current study, although much
more frequently for the Internet group compared with the Maryland group. Although the
Maryland group represents an attempt to sample an entire population, the Internet group
most likely represents an unusually technologically savvy group of audiologists based on the
way the survey was distributed (via Internet
forum and the need to open and save the
attached file, complete the survey, and attach the
survey to a return e-mail message) .
ABR has been established as an efficient
instrument for assessing the vestibulocochlear
nerve and brain stem ; however, its usefulness for
upper brainstem and cortical assessment is limited (Jirsa and Clontz, 1990). Other electrophysiologic tests, which extend beyond the
latency of ABR, show promise in the AP diagnostic process (Kurtzberg, 1989), and their
underuse may be based on lack of familiarity
with longer latency test paradigms and the
applicability of test results to APD diagnosis
and management .
Studies of later potentials have shown
changes in these potentials following AP intervention and have found differences between children with APD and non-APD children . For
example, a study by Jirsa and Clontz (1990) found
significantly longer latency for late evoked potentials in children with APD compared with a normal control group. Jirsa (1992) compared normal
children with children diagnosed with APD and
found a significant difference between the amplitude and latency of the P3 between the normal
controls and the children with APD. Half of the
APD group participated in a 14-week program of
intense listening exercises for auditory memory,
language comprehension, auditory discrimination, attention, and interpretation of auditory
directions . Following the treatment, there was a
significant change in the P3 amplitude and latency
for the treatment group compared with the APD
control group. Kraus and McGee (1994) suggested
that the diagnostic implications of the MMN
include providing an objective measure of auditory discrimination as part of the AP battery.
They presented a series of case studies in which
the MMN was useful in the diagnostic battery to
detect deficits in cortical level processing of auditory discrimination tasks.
106
Attention
ADHD is diagnosed by a psychiatrist or psychologist based on comparing characteristics
displayed by the child with published criteria
(e .g ., Diagnostic and Statistical Manual ofMental Disorders, Fourth Edition; American Psychiatric Association, 1994). The child may fall
into one of three subtypes, including the predominantly inattentive type, predominantly
hyperactive-impulsive type, or a combination
of the two. It is important for audiologists
involved in the diagnosis ofAPD to consider the
possibility of ADHD during AP assessment as
these two disorders may be comorbid or may be
difficult to diagnose differentially (Moss and
Sheiffele, 1994).
According to ASHA (1996), "For some persons, APD is presumed to result from the dysfunction of processes and mechanisms dedicated
to audition; for others, APD may stem from
some more general dysfunction, such as an attention deficit or neural timing deficit, that affects
performance across modalities . It is also possible for APD to reflect coexisting dysfunctions of
both sorts" (p . 41). Children diagnosed with
ADHD and APD may display overlapping behaviors, including difficulty following directions,
asking for directions to be repeated, performing
inconsistently in school, and having difficulty listening, although peripheral hearing sensitivity
is normal . Despite the overlap in behavioral
profiles, Chermak et al (1999) argued that APD
and ADHD are distinct clinical entities that
may sometimes coexist based on neuroanatomic
causes and the possibility that auditory perceptual deficits may trigger attention deficits .
The most commonly reported test of auditory attention for the 30 to 40 percent of respondents who conduct attention tests was the ACPT.
The ACPT reported by 40 percent of Internet
respondents and 18 percent of Maryland respondents, is an auditory vigilance task requiring the
child to listen to a list of words and raise his/her
thumb in response to every presentation of the
word "dog ." The validity of the ACPT has been
examined by comparing differences in performance between children with ADHD with and
without medication (Keith and Engineer, 1991 ;
Tillery et al, 2000) and comparing differences in
performance between children with ADHD and
children without ADHD (Keith, 1994b; Riccio et
al, 1996a) .
Keith and Engineer (1991) found a significant improvement in ACPT performance when
children with ADHD were medicated with
Auditory Processing Battery/Emanuel
methylphenidate compared with the nonmedicated condition; however, they also found
improvements in performance on the SCAN and
Token Tests for children between the two conditions . Their study failed to control for order
effects in that only 1 of their 20 subjects was
tested in the medicated condition first. A later
study that used a counterbalanced design to
control for order effects was conducted by Tillery
et al (2000) . They found that scores on three AP
tests, the SSW, phonemic synthesis (Katz and
Harmon, 1982), and SIN (Mueller et al, 1987),
were not significantly different when children
with ADHD and APD were medicated with
methylphenidate (Ritalin) compared with the
nonmedication condition; however, ACPT scores
were significantly different between groups,
indicating that the medication affected auditory attention but not auditory processing. Riccio et al (1996a) found that children with APD
scored higher than children diagnosed with APD
plus ADHD, but the difference did not reach
significance for this sample . This is in contrast
to an earlier study that showed significant differences between groups (Keith, 1994b) . The
Riccio et al (1996a) study diagnosed APD based
only on the SSW test . This may be a critical
flaw since scores on the SSW may (Gascon et al,
1986 ; Cook et al, 1993) or may not (Riccio et al,
1996b) be affected by attention .
The less frequently reported Vigil and Conners tests are computer-based tests that include
nonverbal stimuli (Vigil includes auditory and
visual) . With current emphasis on the importance of multimodality testing (Hall, 1999 ; Jerger
and Musiek, 2000), these two tests may warrant
further study for use with AP testing.
Multidisciplinary Assessment
The best practice for assessment and management of APD is a team assessment or collaborative approach (ASHA, 1996) . The APD
consensus statement recommended that the
team include an audiologist and speech-language
pathologist at a minimum. The responses to
this survey indicated that a majority of audiologists include professional assessments from
other disciplines as part of their assessment
protocol for AP Although it may not be possible
for an audiologist to perform an on-site observation, the use of questionnaires (previously
discussed), reports from school officials, or communication with the child's teacher regarding
classroom acoustics and format were reported
and can be used in developing recommenda-
tions for children with APD. Auditory memory
tests are infrequently administered by audiologists, presumably because these tests are commonly administered by speech-language
pathologists and psychologists. The most common referral in either the standard or extended
battery from 92 percent of the Internet group and
73 percent of the Maryland group was for a
speech-language evaluation followed by the psychological (76% Internet, 72% Maryland) and
educational evaluations (76% Internet, 72%
Maryland), indicating the importance placed on
the need for an interdisciplinary assessment
team in the assessment and management of
children with difficulties associated with AP.
Test Battery
The results of the survey indicated that
none of the respondents completed all of the
tests recommended by the consensus statement.
There are a number of possible reasons why
clinicians are not following the APD consensus
statement protocol, including the following:
1.
2.
Some tests are not commercially available
(e .g ., gap detection tests using white noise,
localization) . Protocols exist in the published literature but require clinicians to
develop test materials.
Although many AP tests are easily obtainable, many come with little supporting documentation for administration and
interpretation . Normative data may need to
be developed by individual testing facilities
to account for differences in regional dialect,
or normative data may be specific to a particular version of the test (Musiek, personal
communication, July 17, 2001) . Distributors of AP tests often include a disclaimer
with their tests, indicating that administration and scoring information are limited
(or not provided at all) and that purchasers
of AP tests should obtain further information from the literature and/or seminars
(e .g ., Auditec, 1998) .
Although it is true that clinicians who
administer AP tests must have both theoretical and practical knowledge of AP
(ASHA, 1996), it is not surprising that one
of the most commonly reported AP tests
from this and other studies (e .g., Chermak
et al, 1998) is the SCAN (or SCAN-A or
SCAN-C)-a professionally packaged and
marketed test including instructions for
administration and scoring.
107
Journal of the American Academy of Audiology/Volume 13, Number 2, February 2002
3.
Another potential reason for the differences
in test protocol is the heterogeneity of the
population of children with APD. A diverse
and flexible test battery, rather than the
same battery for every child, is essential in
appropriate assessment and management of
these children (Pinheiro and Musiek, 1985 ;
Bellis and Ferre, 1999). Traditional AP testing for adults followed the medical model of
diagnosis to identify pathology. This is evidenced by examining some of the traditional
AP tests, such as the SSW, which includes
extensive documentation for localization of
site of lesion . Many of the reported studies
ofAP test sensitivity and specificity compare
results to a radiologically or surgically diagnosed brainstem and/or cortical pathology
(e .g., Pinheiro, 1976 ; Hurley and Musiek,
1997 ; Musiek et al, 1980 ; Musiek and Pinheiro, 1987). Although APD has been attributed to neurophysiologic disorder (such as
polymicrogyri and heterotopias), neuromaturational differences, neurologic pathology, and trauma (Chermak and Musiek,
1997), many causes of functional deficits
cannot be attributed to a specific pathology. The focus for AP assessment with children should be to determine if the functional
deficits in listening and learning experienced by the child can be attributed to the
auditory system and, if so, how these deficits
can be remediated or managed. The current battery of tests for most clinicians
includes many tests of peripheral and lower
brainstem function, including immittance,
OAE, ABR, and PIPB functions. In contrast,
some of the most exciting research over the
past few decades has focused on cortical
processing; however, these tests are rarely
reported as part of the AP battery.
4. Electrophysiologic tests may not be available
at some audiologic facilities that conduct
AP tests. For example, in a public school system, obtaining electrophysiologic equipment, or referral to an outside agency for
expensive electrophysiologic testing, may
not be considered warranted by the ARD
team, especially considering that APD is
not classified as a disability under the Individuals with Disabilities Education Act as
of the writing of this article. Perhaps more
research on the relationship between electrophysiologic diagnosis and management
outcomes and greater advocacy within the
school system by audiologists performing
AP testing may lead to the evolution of AP
108
testing toward more electrophysiologic testing, including later cortical event-related
potentials .
5. Another potential reason for clinicians not
following the APD consensus statement protocol is the audiologist's prerogative to determine the test protocol that will best benefit
the child based on a review of the literature
and clinical experience . Jerger (1998) indicated in an editorial that he became
"extremely depressed" by the Martin et al
(1998) findings of current audiologic practices. Miller (1998) responded to Jerger's
editorial with the following statement :
"There is a considerable time gap between
publication of new data and their acceptance on the clinical level. Perhaps this is not
,all bad' since it gives us an opportunity to
evaluate what is new (which is not always
good) and to preserve what is old (not always
bad)" (p . 311) . The autonomy of audiologists
relies on our ability to independently consider the merits of our test protocol . Some
audiologists may argue that they do not
agree with the protocol outlined by the
Jerger and Musiek (2000), whereas others
may counter that the use of tests that are
convenient, but do not follow best practices,
is not an example of professional autonomy
but professional inertia (Jerger, 1998).
6. According to Sykes et al (1997), 88 percent
of on-campus clinics in graduate audiology
programs offer APD evaluations; however,
Chermak et al (1998) suggested that university training programs do not adequately
prepare students to assess the central auditory nervous system . Audiologists may not
be using best-practice models of assessment
because of poor training during their graduate education program.
SUMMARY
1.
The typical AP test battery consists of
dichotic speech tests, monaural lowredundancy speech tests, and questionnaires . All audiologists require a basic
audiologic evaluation prior to AP testing,
and most include information from other
professional evaluations (via referral or
on-site team) as part of the APD diagnostic protocol . More than half of the audiologists include temporal processing tests,
and many include ABR as part of their
standard and/or extended test battery, but
few include longer latency potentials .
Auditory Processing Battery/Emanuel
2.
None of the audiologists in this survey
reported using a protocol that met APD
consensus statement guidelines for minimum APD testing . The most often omitted
tests included AMLR, duration pattern,
performance-intensity function, and gap
detection testing .
3.
4.
Tests that are commercially packaged and
accompanied by detailed instructions and
interpretation guidelines (including normative data) such as the SCAN, SCAN-A,
SCAN-C, and ACPT are often the most
widely clinically used tests of APD in each
category.
Many tests are available from commercial
and research facilities or from individual
researchers ; however, the quality of supporting materials varies, and some tests
lack normative and reliability data, especially for children (McFarland and Cacace,
1995). In some cases, published studies are
applicable only to specific versions of the test,
adult listeners, or subjects with a specific
pathology. Individual testing facilities may
need to develop their own normative data
and, in some cases, their own tests to conduct the entire APD battery.
Acknowledgment . The author would like to thank
Dr. Barbara Laufer and Dr. Peggy Oates for their review
of the manuscript and Patricia Lucas for her assistance
during the development of the survey.
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and Stratton, 319-340.
Wiederholt JL, Bryant BR. (2001). Gray Oral Reading
Tests-Fourth Edition (GORT-4). Austin, TX: Pro-Ed.
Willeford JA . (1977). Assessing central auditory behavior in children : a test battery approach . In : Keith RW ed .
Central Auditory Dysfunction. New York : Grune and
Stratton, 43-72 .
Willeford J. (1978) . Sentence tests of central auditory
function . In : Katz J, ed . Handbook of Clinical Audiology.
Baltimore : Williams and Wilkins, 252-261.
Wilson L, Mueller HG. (1984) . Performance of normal
hearing individuals on Auditec filtered speech tests. Am
Speech Lang Hear Assoc 27 :120 .
Auditory Processing Battery/Emanuel
Wilson RH . (1994) . Word recognition with segmentedalternated CVC words: compact disc trials . J Am Acad
Audiol 5:255-258 .
Wilson RH, Arcos JT, Jones HC . (1984) . Word recognition with segmented-alternated CVC words: a preliminary
report on listeners with normal hearing. J Speech Hear
Res 27 :378-387 .
Windham R, Parks M, Mitchener-Colston W. (1986) .
Central auditory processing in urban black children : a
normative study. J Deu Behav Pediatr 7:8-13.
Windham RA . (1985) . Central auditory processing in
urban black children, normal and learning disabled . J
Auditory Res 25 :247-253 .
Woodcock R, Johnson M. (1989) . Woodcock-Johnson
Psycho-Educational Battery-Revised . Tests of Cognitive
Ability. Allen, TX : DLM Teaching Resources.
Wray D, Flexer C, Vaccaro V. (1997) . Classroom performance of children who are deaf or hard of hearing and
who learned spoken communication through the auditory verbal approach : an evaluation of therapy
effectiveness. Volta Rev 99 :107-119.
APPENDIX A
Survey of Audiologists' Central Auditory
Processing (Auditory Processing')
Assessment Battery for Children
(Preschool to Age 18)
1. Do you conduct auditory processing assessments?
Yes
No
If no, please stop here and return the survey. Thank you!
2. Please check your area(s) of certification
and/or licensure.
Audiology
Speech-language pathology
Psychology
_Education
Other. Please specify:
3. Do you usually have a parent, teacher,
and/or client (if age appropriate) complete
a questionnaire for AP evaluations?
No
Yes
If yes, which ones?
"AP" seems to be more appropriate than "CAP" based
on "goals of maintaining operational definitions, avoiding
the imputation of anatomic loci, and emphasizing the interactions of disorders (Jerger and Musiek, 2000). However,
clinical use of "CAP' is still common . For this survey, we
did not wish to confuse clinicians who use the traditional
"CAP" label.
Children's Auditory Performance Scale
Fisher's Auditory Problems Checklist
Screening Instrument for Targeting
Educational Risk
Screening Instrument for Targeting
Educational Risk-Preschool
Other. Please specify :
4. Do you administer monaural lowredundancy speech tests?
No
Yes
Please check all you commonly use as part
of your test battery.
Time-compressed speech test, NU-6
Time-compressed speech test plus reverberation, NU-6
Ivey filtered speech test (Willeford Central Test Battery)
Speech in noise word recognition test
Discrimination of Phonetically Balanced
Kindergarten in Noise
Synthetic Sentence Identification test
with Ipsilateral Competing Message
SCAN-C, Filtered Words
SCAN-A, Filtered Words
SCAN-C, Auditory Figure Ground
SCAN-A, Auditory Figure Ground
-SCAN, Filtered Words
SCAN, Auditory Figure Ground
Low-pass filtered speech test
Pediatric Speech Intelligibility test
Other. Please specify :
5. Do you assess dichotic listening?
Yes
No
Please check all you commonly use as part
of your test battery.
Dichotic Digits test
Staggered Spondiac Words test
Competing Sentences test
_Dichotic Consonant Vowel test
Synthetic Sentence Identification test
with Contralateral Competing Message
_Dichotic Sentence Identification
SCAN-C, Competing Words
SCAN-A, Competing Words
SCAN-C, Competing Sentences
SCAN-A, Competing Sentences
SCAN, Competing Words
Dichotic Rhyme test
Other. Please specify:
113
Journal of the American Academy of Audiology/ Volume 13, Number 2, February 2002
8.
Do you administer electrophysiologic tests as part of your AP battery? Yes
No
Please check tests used as part of the standard test battery and as part of the extended test battery (based on individual client needs) .
Electrophysiologic Tests
Auditory brainstem response
Part of Standard
Test Battery
As Needed, Based on
Individual Case
Otoacoustic emissions
Acoustic reflex threshold
Acoustic reflex decay
Auditory middle latency response
Auditory late response
Mismatched negativity response
P300
Immittance audiometry
Other. Please specify:
6. Do you test temporal processing (e .g ., temporal ordering, gap detection)?
Yes
No
Please check all you use as part of your test
battery.
Pitch Pattern Sequence
Pitch Pattern Sequence-Child Version
Duration Pattern Test
Intensity Pattern Sequence Test
Gap detection test
Auditory Fusion Test
Psychoacoustic Pattern Discrimination
Test
Other. Please specify:
7. Do you assess binaural interaction?
Yes
No
Please check all you use as part ofyour test
battery.
Rapidly Alternating Speech Perception
Binaural Fusion Test (Willeford Central
Test Battery)
Masking level difference
Binaural Fusion (bandpassed), NU-6
Segmented-alternated consonant-vowelconsonant fusion test
Other. Please specify:
114
Do you assess localization and/or lateralization?
Yes
No
How?
9 . Do you assess auditory attention?
Yes
No
Please check all you use as part of your test
battery.
Auditory Continuous Performance Test
Conners' Continuous Performance Test
Vigil Continuous Performance Test
Selective Auditory Attention Test
Other. Please specify:
10 . Do you routinely perform a classroom
observation/assessment?
Yes
No
If yes, do you fill out an evaluation as part
of the observation/assessment?
Yes
No
What type of evaluation do you complete?
11 . Do you assess memory?
Yes
No
Please check all you use as part of your test
battery.
Test of Auditory-Perceptual SkillsRevised
Auditory Number Memory
Auditory Number-Reverse Memory
Auditory Processing Battery/Emanuel
Auditory Sentence Memory
Auditory Word Memory
Goldman-Fristoe-Woodcock Auditory
Memory Test
Recognition Memory
Memory for Content
Memory for Sequence
Denver Auditory Phoneme Sequencing
Auditory Sequential Memory Test
Other. Please specify :
12 . Do you require a basic audiologic assessYes
No
ment prior to AP testing?
Please check all you require prior to (or during) AP assessment .
Otoscopic evaluation
Pure-tone air-conducted/bone-conducted
evaluation
Speech recognition threshold
Word recognition
Sentence recognition
Nonsense syllable recognition
Performance-intensity function
Tympanometry
Other. Please specify:
13 . Do you administer speech-language and/or
psychoeducational tests as part of your AP
test battery?
Yes
No
Please check all you use as part of your test
battery.
Test of Auditory Perceptual Skills
Auditory Interpretation of Directions
Auditory Word Discrimination
Auditory Processing
Goldman-Fristoe-Woodcock Auditory
Skills Battery
-Quiet Subtest
Noise Subtest
Lindamood Auditory Conceptualization
Test
Isolated Sounds in Sequence
Sounds within a Syllable Pattern
Auditory Discrimination Test
Test for Auditory Comprehension of
Language-3
Vocabulary
Grammatical Morphemes
Elaborated Phrases and Sentences
Token Test for Children
Part I-two critical elements
Part II-four critical elements
Part III-three critical elements
Part IV-six critical elements
-Part V-linguistic concepts
Flowers-Costello Test of Central Auditory Abilities
Woodcock-Johnson Psychoeducational
Battery-Revised
Clinical Evaluation of Language Fundamentals-Revised
Phonological Awareness Screen
Other. Please specify:
15 . Would you like a copy of the results of this
survey?
Yes
No
Thank you for your time . Please return the
completed survey in the enclosed SASE or mail
to Dr. Diana Emanuel, Department of Communication Sciences and Disorders, Towson University, 8000 York Rd ., Towson, MD 21252-0001 .
If you receive this survey electronically, please
attach your response and send it to
[email protected] .
14 . What other evaluations (via referral or on-site team) are part of your AP diagnostic protocol?
Type of Evaluation
Part of Standard Test Battery I As Needed, Based on Individual Case
Psychological
Educational
Speech-language
Otolaryngology
Neurologic
Other. Please specify :
Journal of the American Academy of Audiology/Volume ~13, Number 2, February 2002
APPENDIX B2
American Guidance Service
4201 Woodland Road
P.O . Box 99
Circle Pines, MN 55014-1796
800-328-2560
www.agsnet.com
0
"
"
"
Comprehensive Assessment of Spoken Language
Goldman-Fristoe-Woodcock Test ofAuditory
Discrimination
Oral and Written Language Scales
Peabody Picture Vocabulary Test-III
Audiology Illustrated, LLC
111 Lyme Road
Hanover, NH 03755
603-643-9705
"
"
"
Dichotic Digits
Frequency Patterns
Duration Patterns
Auditec of St . Louis
2515 S. Big Bend Blvd .
St . Louis, MO 63143
314-781-8890
800-669-9065
www. auditec. com
"
"
Auditory Fusion Test-Revised
Competing Sentences
"
"
"
"
Dichotic Digits
Dichotic Sentence Identification
Dichotic Word Listening Test
Discrimination of Phonetically Balanced
Kindergarten in Noise
Duration Pattern Sequence (DPS)
Low-pass filtered lists; NU-6, PBK-50, Word
Intelligibility by Picture Identification
NU-6 with various competitions
Pediatric Speech Intelligibility Test
Pitch Pattern Sequence
Random Gap Detection Test
Rapid Alternating Speech
Selective Auditory Attention Test
Speech in Noise
Spondee Binaural Fusion
Synthetic Sentence Identification with Contralateral Competition
Synthetic Sentence Identification with Ipsilateral Competition
"
"
"
"
"
"
"
"
"
"
"
Dichotic CV
2 Many of the speech-language tests are available from
multiple distributors but are only listed once .
116
"
Time-compressed speech (several standard
word recognition score lists including WIPI)
Educational Audiology Association
4319 Ehrlich Rd .
Tampa, FL 33624
www.edaud .org
800-460-7EAA
Children's Auditory Performance Scale
Fisher Auditory Problems Checklist
Listening Inventory for Education
Screening Identification for Targeting Educational Risk
Etymotic Research
61 Martin Lane
Elk Grove Village, IL 60007
847-228-0006
"
Quick SIN
Linguisystems
3100 4th Avenue
RO. Box 747
East Moline, IL 61244-0747
www.linguisystems .com
800-776-4332
Fax: 800-577-4555
"
Phonological Awareness Test
Maico Diagnostics
9675 West 76th Street
Eden Prairie, MN 55344
952-941-4201
Fax: 952-903-4200
www.maico-diagnosties .com
"
Hearing in Noise Test
Precision Acoustics
411 NE 87th Avenue, Suite B
Vancouver, WA 98664
360-892-9367
"
"
"
"
Competing Environmental Sounds
Phonemic Synthesis
Phonemic Synthesis Picture
Staggered Spondaic Word
Pro-Ed
8700 Shoal Creek Boulevard
Austin, TX 78757-6893
800-897-3202
Fax: 800-397-7633
www.proedinc .com
"
Comprehensive Test of Phonological Processing
Auditory Processing Battery/Emanuel
0
0
Detroit Test of Learning Aptitude-Fourth
Edition
Expressive One Word Picture Vocabulary
Test-2000 Edition
Gray Oral Reading Tests-Fourth Edition
Lindamood Auditory Conceptualization Test
Test for Auditory Comprehension and Language, Third Edition
Test of Auditory Perceptual Skills-Revised
Test of Phonological Awareness
Test of Word Finding, Second Edition
Test of Written Language, Third Edition
Token Test for Children
The Psychological Corporation
555 Academic Court
San Antonio, TX 78204-2498
800-872-1726
www.psychcorp .com
"
0
0
0
0
0
Vigil Continuous Performance Test (Psychological Corporation, 1996)
Conners' Continuous Performance Test (Conners, 1994)
Auditory Continuous Performance Test
(ACPT) (Keith, 1994b)
SCAN-C : Test for Auditory Processing Disorders in Children (Keith, 2000)
SCAN-A : A Test for Auditory Processing
Disorders in Adolescents and Adults (Keith,
1994a)
SCANWARE (Software)
Test of Phonological Awareness
Clinical Evaluation of Language Fundamentals, Third Edition
Photo Articulation Test, Third Edition
Read America
Box 1246
Mount Dora, FL 32756
352-735-9292
Fax: 001-352-735-9294
www.ReadAmerica .net
RAchat@aol .com
"
Phono-Grapix
Riverside Publishing Company
425 Spring Lake Drive
Itasca, IL 60143-2079
800-323-9540
http ://www.riverpub.com
"
Test of Word Finding in Discourse
Slosson Educational Products
P.O . Box 280
East Aurora, NY 14052-0280
888-756-7766
800-655-3840
"
Slosson Oral Reading Test
Western Psychological Services
12031 Wilshire Boulevard
Los Angeles, CA 90025-1251
310-478-2061
www.wpspublish .com
"
Auditory Discrimination Test
Richard Wilson, PhD
Chief, Audiology
James H. Quillen VA Medical Center
Mountain Home, TN 37684
www.va .gov/621quillen/clinics/asp
(Use this Web site to download word lists for the
compact disc .)
Richard.Wilson2Qmed .va.gov
Tonal and Speech Materials for Auditory Perceptual Assessment
Dichotic Digits
Dichotic Consonant Vowels
Dichotic synthetic sentences
NU-6 high-pass filter
Frequency patterns
NU-6 compression + reverberation
Spondaic words masking level difference
Speech Recognition and Identification Materials
"
"
"
Competing Sentences
NU-6 in babble
SSI-ICM
Jack A. Willeford, PhD
4603A E. 2nd Street
Tucson, AZ 85711
520-290-0158
0
Willeford Battery