Measuring Intelligibility in Dysarthria:
The Need for Adding Some Adjectives
Kathryn M. Yorkston,
PhD, BC-NCD
Rehabilitation Medicine
Overview
z
z
z
Define – Listener generated intelligibility
measurement
Place intelligibility within ICF framework
Illustrate various types of intelligibility
–
–
–
Understand impairment
Association with restricted participation
Identify contextual factors
Definition: Intelligibility
z
z
z
z
Dictionary – “capable of being understood”
The extent that [ _____ ] is understood by
[ _____ ]
Adjectives define the [ _____ ]’s
Listener generated measures used in clinical
decision making
Intelligibility with Adjectives
z
What’s the utterance?
–
–
–
Paragraphs
Sentences
Words in sentences
z
z
–
–
High predictability
Low predictability
Words
Phonemes in words
Intelligibility with Adjectives
z
What’s the listening condition?
–
–
–
z
Supplemented with context
Supplemented with 1st letter identification
Degraded with noise
Who is listening?
–
–
–
–
Age
Familiarity
Gender
Better vs poorer listener
Normal Ogive Curve
Intelligibility
Curve
(Item Characteristic Curve)
1
0.9
0.8
Intelligibility
Response Odds
0.7
0.6
Easy
Task
0.5
Hard
Task
0.4
0.3
0.2
0.1
0
-3
Profound
-2
-1
0
1
Trait Level (Logits)
Severity
Level
2
3
Mild
ICF Framework
Health Condition
Body
Functions
Environmental
Factors
Activity
Participation
Personal
Factors
Health Condition
Body
Impairment
Functions
Environmental
Factors
Activity
Activity
Limitation
Participation
Participation
Restriction
Personal
Factors
Dysarthria & ICF
Speech Subsystems
Body
● Resp/phon
Impairment
Functions
● VP
● Articulation
Health Condition
Speech
Adequacy
Activity
Activity
Intel, rate
Limitation
Naturalness
Environmental
Factors
Interference
with
Participation
Participation
taking part
Restriction
in life situations
Personal
Factors
ICF Framework, WHO, 2001
Phoneme
Intell
Health Condition
Body
Impairment
Functions
Environmental
Factors
Participation
Activity
Participation
Phoneme
Restriction
Can phoneme
intelligibility
Intell.
tell us something
about the
impairment?
Personal
Factors
Consonant Matrix Report
Summary Report
Without Lift
With LIft
Without Lift
With Lift
Pressure Consonants
Percent
Correct
Nasal Consonants
80
80
70
70
60
60
50
50
Percent
Correct
40
40
30
30
20
20
10
10
0
0
23
23.5
24
MPO
24.5
25
23
23.5
24
MPO
24.5
25
Health Condition
Body
Impairment
Functions
Environmental
Factors
Activity
Sentence
Intell.
Participation
Participation
Restriction
Personal
Factors
ICF Framework, WHO, 2001
Assessment Procedures
z
Activity Limitation (Execution of a task)
z
Speech Intelligibility (Yorkston, Beukelman & Tice, 1996)
– Speech Rate
Participation Restriction (Restrictions in life situations)
–
–
Communication Effectiveness (Yorkston, Beukelman, Strand & Bell, 1999)
z
z
z
z
Having a conversation with a few friends.
Conversing with a familiar person on the telephone.
Being part of a conversation in a noisy environment (social gathering)
Having a conversation while traveling in a car.
Sentence Intelligibility Test
Sentence Intelligibility Test
Sentence Intelligibility Test
Sentence Intelligibility Test
Sentence Intelligibility Test
Ball, 2004
Health Condition
Body
Impairment
Functions
Environmental
Factors
Intell.
Activity
In
Context
Participation
Participation
Restriction
Personal
Factors
ICF Framework, WHO, 2001
Alphabet cues
Habitual
100
Sentence
Intelligibility
80
60
40
Hanson, 2004
20
0
0
Most
5
10
15
Severity Ranking
20
Least
25
Habitual
Semantic Cues
100
Word
Intelligibility
80
60
40
Hanson, 2004
20
0
0
Most
5
10
15
20
Severity Ranking
25
30
Least
35
With context
Word Intelligibility
With Context
Word Intelligibilty
Case 2
Case 1
100
100
80
80
60
60
Percent
Correct
Percent
Correct
40
40
20
20
0
0
Familiar
Unfamiliar
Partner
Familiar
Unfamiliar
Partner
Health Condition
Body
Impairment
Functions
Activity
Intelligibility
Environmental
Factors
Participation
Participation
Restriction
Personal
Factors
ICF Framework, WHO, 2001
References
z
z
z
Ball, L. J., Beukelman, D. R., & Pattee, G. (2004). Communication
effectiveness of individuals with amyotrophic lateral sclerosis.
Journal of Communication Disorders, 37(3), 197-215.
Dorsey, M., Yorkston, K., Beukelman, D., & Hakel, M. (2007).
Speech intelligibility test for windows. Lincoln, NE: Institute for
Rehabilitation Science and Engineering at Madonna Rehabilitation
Hospital.
Hanson, E. K., Yorkston, K. M., & Beukelman, D. R. (2004).
Speech supplementation techniques for dysarthria: A systematic
review. Journal of Medical Speech-Language Pathology, 12(2), ixxxix.
References (continued)
z
z
z
World Health Organization. (2001). International classification of
functioning, disability and health (icf). Geneva, Switzerland:
Author.
Yorkston, K. M., Beukelman, D. R., Strand, E. A., & Bell, K. R.
(1999). Management of motor speech disorders in children and
adults (2nd ed.). Austin, TX: Pro-Ed.
Yorkston, K., Beukelman, D., Hakel, M., & Dorsey, M. (2007).
Speech intelligibility test for windows. Lincoln, NE: Institute for
Rehabilitation Science and Engineering at Madonna Rehabilitation
Hospital..