Clinical
ORIGINAL ARTICLE
Field evaluation of the CRT and ACON chlamydia
point-of-care tests in a tropical, low-resource setting
D S Hurly,1 M Buhrer-Skinner,1 S G Badman,2 S Bulu,3 S N Tabrizi,4,5,6
L Tarivonda,7 R Muller1,8
For numbered affiliations see
end of article.
Correspondence to
Dr Dermot Hurly, PO Box 585,
Oneroa, Auckland,
New Zealand;
[email protected]
Received 19 June 2013
Revised 1 October 2013
Accepted 10 November 2013
Published Online First
13 December 2013
ABSTRACT
Objective To evaluate the clinical performance of two
chlamydia point-of-care (POC) tests compared with a
gold standard nucleic acid amplification testing (NAAT).
Methods Tests evaluated were the Chlamydia Rapid
Test (CRT), Diagnostics for the Real World and the
ACON Chlamydia Rapid Test Device, ACON Laboratories
(ACON). Overall 226 men and 225 women in Port Vila,
Vanuatu, participated in this prospective study in 2010.
NAAT and POC testing was performed on samples of
male urine and female vaginal swabs for 156 men and
223 women (CRT), and 133 men and 75 women
(ACON).
Results The sensitivity and specificity of the CRT in
men were 41.4% (95% CI 23.5% to 61.1%) and
89.0% (95% CI 82.2% to 93.8%), respectively, and in
women 74.2% (95% CI 61.5% to 84.5%) and 95.7%
(95% CI 91.3% to 98.2%), respectively; for ACON, they
were 43.8% (95% CI 19.8% to 70.1%) and 98.3%
(95% CI 93.9% to 99.8%) in men, and in women
66.7% (95% CI 22.3% to 95.7%) and 91.3% (95%
CI 82.0% to 96.7%), respectively. Both tests were
(absolutely) insensitive at organism loads less than 1000
(log=3) per mL or per swab; the CRT sensitivity was
significantly lower at loads less than, compared with
those greater than, 100 000 (log=5) per mL or per
swab.
Conclusions The performance of both CRT and ACON
is well below the levels stated by the manufacturers. The
evaluated tests are unlikely to be helpful in clinical
settings due to the high proportion of false-negatives
that will go untreated and false-positives that will result
in overtreatment and potential adverse social
consequences.
INTRODUCTION
▸ http://dx.doi.org/10.1136/
sextrans-2013-051445
To cite: Hurly DS,
Buhrer-Skinner M,
Badman SG, et al. Sex
Transm Infect 2014;90:
179–184.
Chlamydia trachomatis is the commonest notifiable
bacterial sexually transmitted infection (STI) in the
world, with the WHO estimating 105.7 million
cases worldwide in 2008.1 Chlamydial infection is
associated with reproductive morbidity, including
pelvic inflammatory disease, infertility, chronic
pelvic pain, ectopic pregnancy and adverse pregnancy outcomes,2 and is a cofactor in HIV transmission.3 4
Port Vila is the capital of the tropical Pacific
island nation of Vanuatu, which had a population
of 234 000 in 2009.5 Vanuatu has a high prevalence of chlamydia, similar to the region as a
whole.6 Overall prevalence of chlamydia in Pacific
antenatal populations has been reported at 18% in
6 countries in 20057 and at 19% in 11 countries in
Hurly DS, et al. Sex Transm Infect 2014;90:179–184. doi:10.1136/sextrans-2013-051246
2007and 20086; surveys in Vanuatu have variously
found prevalences of 21.5%, 13.2% and 25.1% in
antenatal populations in 2000, 2005 and 2008,
respectively.8 9
Screening is needed to detect chlamydial infections that are often asymptomatic,10 while early
diagnosis and treatment is important for patients
who present with symptoms. Syndromic management remains the mainstay of diagnosis and treatment in many developing countries. While
reasonable sensitivities for male urethral discharge
(87–99%) and ulcerative disease (68–98%) have
been reported,11 it performs less well for symptoms
of vaginal discharge with sensitivities reported
from 30 to 80% and specificities from 40 to
80%12; false-positive diagnoses lead to overtreatment and potential adverse social consequences.13
Although DNA-based laboratory testing with
high sensitivity and specificity may be available in
developing countries, it is often not affordable nor
accessible to patients; it requires patients to return
to obtain results and treatment, resulting in loss of
follow-up
and
delays.14
Well-performing
point-of-care (POC) tests offer a ‘test and treat’
approach in one visit and potentially offer a major
advantage over laboratory-based and syndromic
management, particularly where the return for
treatment is low.10 15 16
We independently evaluated the diagnostic performance of two chlamydia POC tests, with the manufacturers’ stated sensitivity and specificity for each
test above 82% and 96%, respectively. The
immunoassay-based tests evaluated were ‘Chlamydia
Rapid Test’ (CRT) and the ACON ‘Chlamydia Rapid
Test Device’ (ACON), manufactured by Diagnostics
for the Real World (DRW) and ACON Laboratories,
respectively.
METHODS
Evaluation study
The presented evaluation study was part of a larger
intervention study on the utility of POC tests for
the management of chlamydia in Port Vila,
Vanuatu. The tests for this evaluation study were
conducted during the first and second phases of the
intervention study.
Independence of the study
The study was independent, with neither manufacturer involved in study design, implementation,
analysis or manuscript writing. Test kits were purchased at market price from the manufacturers at
their developing country rates.
179
Clinical
Setting
The KPH Clinic is one of two reproductive health clinics in
Port Vila. In total, 4155 clients accessed KPH Clinic services in
the calendar year of 2010, 84% being women and 16% men,
and 43% were under the age of 25. Most (55%) attended for
family planning services, 20% for STI services and 20% for
counselling on a variety of reproductive health matters; 44 commercial and opportunistic sex workers attended the clinic.
Ethics
Ethics approvals for all parts of the study were obtained from
the Vanuatu Ministry of Health, Port Vila, Vanuatu and the
Ethics Committee of James Cook University, Queensland,
Australia.
advised to insert the swab 4–5 cm into the vagina and rotate it
10 times, and immediately place the swabs within the provided
containers. Either two swabs (CRT+NAAT) or three swabs
(CRT, ACON and NAAT) were taken; the collection order for
the swabs taken was (1) CRT, (2) ACON and (3) NAAT (ACON
manufacturer’s instructions are for a cervical—not vaginal—
swab).
Rapid testing commenced within the hour of sample collection. Swabs and centrifuge-generated urine pellets were
extracted after adding the supplied reagents and using fixed
volume disposable plastic pipettes; the resultant solution was
then added to the test cartridges in accordance with the manufacturers’ package instructions.
Reading of results
Recruitment and data collection
Men and women attended the clinic either by self-referral or
community outreach. Consecutive patients over the age of 18
were invited to participate in the study between April and
November 2010 (the study period) on evaluation days over two
phases of testing and treatment. Written informed consent was
obtained from literate participants; detailed and standardised
information was read to those illiterate. Exclusion criteria were
antibiotic treatment within the past month, previous participation and menstruation. Participants were interviewed by a nurse
using a fully structured questionnaire. Information was collected
on demographic and clinical data.
Training and environmental control
Strict clinical and laboratory handling and decontamination procedures were implemented. Procedures for storage and use of
kits between 2 and 30°C, as well as collection and testing procedures, were conducted in accordance with the rapid tests manufacturer’s instructions. Nurses were trained in CRT testing prior
to the commencement of the study using ‘familiarisation’ panels
with samples of varying concentrations of chlamydia antigen,
and their competence assessed by successfully analysing samples
from similar ‘proficiency’ panels; the panels were supplied by
DRW.
Specimen collection and testing
The test evaluations were based on male urine and female
vaginal swabs. CRT testing was performed through the first
phase of the study evaluating prevalent infection and through
the second phase evaluating incident infection. ACON testing
commenced towards the end of the first phase and continued
through the second phase.
Men collected one or two initial void samples for CRT and/or
ACON testing in either the initial 4–5 mL of urine in a ‘First
Burst’ device (CRT) or 15–20 mL in a sterile container (ACON)
after a non-voiding period of at least 2 h for each sample. The
First Burst yields an approximately sixfold higher organism load
per mL of urine than a routine cup-collected specimen.17
Where two samples were collected for CRT and ACON, collection order was alternated. A 0.5–1 mL aliquot of urine was
taken for nucleic acid amplification testing (NAAT) prior to the
centrifugation of aliquots of urine with distilled water for CRT
and ACON testing as per the manufacturer’s instructions to
obtain a centrifuge-generated urine pellet.
All women were instructed and encouraged to self-collect
vaginal swabs; in some instances, a vaginal swab was taken by a
nurse. Swabs from the rapid test kits were used for female rapid
testing, and flocked swabs used for NAAT testing. Women were
180
Rapid tests were interpreted qualitatively as per CRT and
ACON manufacturers’ instructions. An additional reading was
done by comparing the visual signal of both tests with a signal
scale (0.5–5, in increments of 0.5) on a card provided by DRW.
Where there was uncertainty in the strength of the visual signal,
a second nurse was consulted and consensus reached. Tests were
considered invalid if a control line was not visible.
NAAT testing
Urine and swab samples were frozen on the same day and sent
to the Royal Women’s Hospital, Melbourne, for testing. Upon
arrival, nucleic acid was extracted from the 200 mL aliquot of
urine or swab rotated in phosphate buffered saline on the automated MagNA Pure LC (Roche Applied Science, Mannheim,
Germany) using the MagNA Pure DNA I Isolation Kit (Roche
Applied Science) according to the manufacturer’s protocol with
the DNA eluted in 100 mL of Elution Buffer (Roche Applied
Science). PCR was carried out with 25 mL of extracted DNA on
the COBAS TaqMan 48 PCR assay (Roche Diagnostic,
Branchburg, New Jersey, USA) according to the manufacturer’s
instructions.
All chlamydia-positive samples were tested for chlamydial
load by a quantitative PCR (qPCR) system targeting the omp1
gene using published methodology.18 The chlamydial load in
each sample was estimated by comparing the crossing threshold
of each sample to the crossing threshold of a standard curve
constructed by amplifying different known copy numbers of the
omp1 gene.
Statistical analysis
All statistical analyses were conducted using IBM SPSS Statistics
for Windows, V.20. Age of participants was summarised using
median values and IQR. Categorical data were summarised
using absolute and relative frequencies. Comparisons between
variables were conducted by χ2 and Wilcoxon bivariate statistical
tests as appropriate; the α level was set at 0.05 for all tests.
The prevalence of chlamydia, and the sensitivities and specificities for each test, is presented together with exact binomial
95% CIs.
RESULTS
Study population
Altogether 379 unique individuals (156 men and 223 women)
had valid CRT + NAAT testing, and 207 unique individuals
(132 men and 75 women) had ACON+NAAT testing; there
were 14 people who had missing rapid or NAAT test results.
The median age was 25 years. See table 1 for further details and
for patient-reported symptoms.
Hurly DS, et al. Sex Transm Infect 2014;90:179–184. doi:10.1136/sextrans-2013-051246
Clinical
Table 1 Characteristics of the study populations
Characteristic
CRT (N=379), n (%)
ACON (N=207), n (%)
Median age (IQR),
range in years
Gender
Male
Female
Male self-reported symptoms
Dysuria
Urethral discharge
Scrotal pain
Any symptom above
No data
Female self-reported symptoms
Vaginal discharge
Lower abdominal pain
Any symptom above
No data
25.0 (21.0–30.0),
18–60
25.0 (21.25–30.0),
18–56
156 (41.2%)
223 (58.8%)
N=154
60 (39.0%)
42 (27.3%)
33 (21.4%)
74 (48.1%)
2
N=213
103 (48.4%)
113 (53.1%)
130 (61.0%)
10
132 (63.8%)
75 (36.2%)
N=66
4 (6.1%)
4 (6.1%)
1 (1.5%)
6 (9.1%)
66
N=66
14 (21.2%)
19 (28.8%)
24 (36.4%)
9
CRT, Chlamydia Rapid Test.
Prevalence of chlamydia and rapid test performance
There were no invalid rapid tests.
The prevalence by NAAT for men and women tested by CRT
was 18.6% and 27.8%, respectively, estimating prevalent infections in the population tested during the first phase of the intervention study; for ACON, it was 12.1% and 8.0%, respectively,
estimating incident and untreated chlamydial infections occurring during the second phase.
Comparing the test quality criteria between genders, the CRT
male sensitivity of 41.4% is significantly less than the CRT
female sensitivity of 74.2%. All other listed gender differences
are not significant at an α level of 0.05. Of those truly positive
by NAAT, 72.4% and 33.3% of men tested by CRT and ACON,
respectively, had self-reported symptoms; similarly 66.7% and
40.0% of NAAT-positive women tested by CRT and ACON,
respectively, were symptomatic. See table 2 for details.
Organism load
The median organism loads (table 3) differed significantly
between females and males, with loads in females higher than in
males by a (linear) factor of 14 in the CRT population and of
72 in the ACON population (the CRT ‘First Burst’ device concentrates the load by approximately sixfold).
POC sensitivity and organism load
Both tests were absolutely insensitive at organism loads below
1000 (log=3) per mL or swab. Sensitivities of the CRT male
and female tests at loads less than 100 000 (log=5) per mL or
per swab were 23.8% (95% CI 8.22% to 47.2%) and 58.8%
(95% CI 40.7% to 75.4%); at loads greater than 100 000
(log=5), they were significantly different ( p<0.05) at 87.5%
(95% CI 47.4% to 99.7%) and 92.9% (95% CI 76.5% to
99.1%), respectively.
Figure 1 displays a scatter plot of the relationship between
CRT visual signals and organism loads determined by the
NAAT test.
POC specificity
By reclassifying the weak positive (0.5) POC visual signals as
negative, the CRT specificities increased in men and women to
97.6% (95% CI 93.3% to 99.5%) and 98.8% (95% CI 95.6%
to 99.9%), respectively, with a reduction in sensitivity to 27.6%
(95% CI 12.7% to 47.2%) and 64.5% (95% CI 51.3% to
76.3%), respectively; similarly in ACON the specificities in men
and women were 100% (95% CI 96.9% to 100%) and 100%
(95% CI 94.8% to 100%), respectively, and the sensitivities
were 31.3% (95% CI 11.0% to 58.7%) and 50.0% (95% CI
11.8% to 88.2%), respectively.
DISCUSSION
POC sensitivity
The sensitivity of the male CRT test of 41.4% (95% CI 23.5%
to 61.1%) was substantially and statistically significantly lower
than the 82.6% (95% CI 75.4% to 89.7%) stated in the manufacturer’s package insert. The sensitivity of the female CRT test
of 74.2% (95% CI 61.5% to 84.5%) was lower than the manufacturer’s stated 83.5% (95% CI 76.5% to 90.5%) for women,
but not significantly so. CRT detected fewer infections in men
(41.4% (95% CI 23.5% to 61.1%)) than would have been
determined by self-reported symptoms alone (72.4% (95% CI
52.7% to 87.27%)), and similar numbers of infections in
women (74.2% (95% CI 61.5% to 84.5%) and 66.7% (95% CI
54.6% to 79.1%)), respectively.
We found a distinct relationship between organism load and
CRT performance, which probably resulted in the poorer performance in the male CRT (men having a significantly lower
load than women).
Four publications on CRT performance authored between
2007 and 2009 reported CRT sensitivities for male ‘First Burst’
urine between 82% and 82.6%,17 19 and for CRT female
vaginal swabs between 71% and 86.8%;20 21 a systematic
review of these studies reported pooled estimates of CRT sensitivity and specificity for male first-void urine specimens to be
77% and 99%, and for female vaginal swabs to be 80% and
99%.22
Our findings, however, are more in keeping with a later, and
the only other independent, study of the CRT used for
Table 2 Prevalence by nucleic acid amplification testing (NAAT), point-of-care (POC) performance and sensitivity of symptoms compared with
NAAT for males and females tested by Chlamydia Rapid Test (CRT) and ACON
Prevalence by NAAT
POC sensitivity
POC specificity
Sensitivity of
self-reported
symptoms*
CRT male
(%), 95% CI
CRT female
(%), 95% CI
ACON male
(%), 95% CI
ACON female
(%), 95% CI
18.6%
41.4%
89.0%
72.4%
27.8% (62/223) (22.0% to 34.2%)
74.2% (46/62) (61.5% to 84.5%)
95.7% (154/161) (91.3% to 98.2%)
66.7% (42/62) (54.6% to 79.1%)
12.1%
43.8%
98.3%
33.3%
8.0%
66.7%
91.3%
40.0%
(29/156) (12.8% to 25.6%)
(12/29) (23.5% to 61.1%)
(113/127) (82.2% to 93.8%)
(21/29) (52.7% to 87.27%)
(16/132) (7.1% to 18.9%)
(7/16) (19.8% to 70.1%)
(114/116) (93.9% to 99.8%)
(2/6) (4.33% to 77.7%)
(6/75) (3.0% to 16.6%)
(4/6) (22.3% to 95.7%)
(63/69) (82.0% to 96.7%)
(2/5) (5.2% to 85.3%)
*Male dysuria and/or urethral discharge and/or scrotal pain; female vaginal discharge and/or lower abdominal pain.
Hurly DS, et al. Sex Transm Infect 2014;90:179–184. doi:10.1136/sextrans-2013-051246
181
Clinical
Table 3 Organism load for all men and women positive by
nucleic acid amplification testing and tested by Chlamydia Rapid
Test (CRT) and ACON (copies/mL or copies/swab)
Organism
load
CRT
Median (IQR)
log median
(IQR)
ACON
Median (IQR)
log median
(IQR)
Male
Female
p Value
n=29
6010 (1465–186 500)
log: 3.78 (3.17–5.27)
n=62
83 400 (19 750–245 600)
log: 4.92 (4.30–5.39)
<0.006
n=16
2200 (700–21 500)
log: 3.34 (2.85–4.33)
n=6
158 000 (94 600–
555 000)
log: 5.2 (4.98–5.74)
<0.001
urogenital testing; in 2012, Van der Helm reported a sensitivity
of 41.2% in female nurse-collected vaginal swabs, with a higher
test sensitivity found with higher organism loads.23
On further examination, our results may be consistent with
some findings in the four earlier publications. Wisniewski
et al,17 in an evaluation of the male CRT, noted that sensitivity
improved from 47% to 82% due to a sixfold increase in organism load obtained from First Burst-collected urine compared
with cup-collected urine; they noted that the sensitivity of CRT
correlated directly to the chlamydial load.
Mahilum-Tapay et al,21 in a performance evaluation of the
female CRT, performed quantitative testing for 33/56
PCR-positive swabs and noted that the rapid test visual signal
correlated with organism load. It is also apparent from the
graph provided that 30 of these 33 samples had organism loads
greater than 100 000 (log=5) plasmids/swab and the median
load was greater than 1 000 000 (log=6) plasmids/swab; our
female CRT population had a median load of 83 400
(log=4.92) copies/swab. Similarly, Nadala et al19 performed
quantitative testing on 80/90 urine samples collected from men
by First Burst. It is apparent from the graph provided that the
median organism load was greater than 100 000 (log 5) plasmids/mL; our median organism load for First Burst-collected
urine was 6010 (log=3.78) copies/mL.
Performance characteristics for NAAT may vary depending on
the organism load of patients in the study, the reference standard used and the assay under evaluation. While some differences
in the organism loads between the previous evaluation studies
and our study may be explained by the different assays used, the
Figure 1 Relationship between organism load and Chlamydia Rapid
Test signal strength (nucleic acid amplification testing positive cases).
182
data also suggest that the loads found in our population may be
lower than those found in those studies. Other authors have
found evidence that loads can vary between prevalent and incident infections,24 and between community and clinic
populations.25
Furthermore, Michel et al found in 201126 that the sensitivity
of a similar DRW-manufactured chlamydia lipopolysaccharide
POC test for ocular trachoma was 30.4%, substantially less than
the 83.6% published earlier by Michel et al27; the difference
was explained by a lower organism load. In an independent
study, also published in 2011, Harding-Esch et al28 found that
the sensitivities of this test ranged between 33.3% and 67.9%.
The found ACON sensitivity for the male urine of 43.8%
(95% CI 19.8% to 70.1%) compared poorly to the manufacturer’s stated 90.9%. The ACON female vaginal swabs sensitivity of 66.7% is not directly comparable to the manufacturer’s
stated 88.5% for cervical swabs due to a potential twofold to
threefold reduction in organism load in vaginal compared with
cervical samples.29 The number of truly positive ACON participants with symptoms was too small to make inferences about
the sensitivity of symptoms.
POC specificity
Specificities for CRT in men and women were 89.0% and
95.7%, respectively, which are less than the manufacturer’s
stated 98.5% and 98.9%, but not significantly different; similarly, ACON specificities were 98.3% and 91.3%, less than the
manufacturer’s stated 99% and 96.7%, respectively, but not significantly different.
It is possible that temperature affects POC specificity; the
independent study of the ocular POC test manufactured by
DRW found specificity to decrease markedly with temperatures
above 31.4°C and with lower relative humidity.28 While our
maximum storage and laboratory temperatures did not exceed
the recommended 30°C, they were likely to be higher than
those found in the temperate zones where the tests were mostly
evaluated.
It is also possible that weak positive visual signals (0.5) were
over-read by our staff. By classifying all such weak signals as
negative, specificity increased to greater than 97.6% for all POC
tests; however, there is a consequent fall in sensitivity, ranging
from 27.6% to 64.5% for all tests.
Potential for bias
Our sample was self-selected through attendance at a clinic and
through invitation via community outreach, with a potential for
selection bias. Consecutive patients were invited to participate,
reducing the potential for this type of selection bias; however, it
cannot be seen how even a strong selection bias could influence
the quality criteria of the tests unless via organism load as discussed previously.
There were a number of potential causes for information
bias; our POC tests were read by a single nurse, without a blind
reading from a second nurse, which could lead to a classification
bias for the POC tests. We believe this would be unlikely to
have affected the sensitivity and specificity readings for the tests
as all nurses proved competence in interpreting the tests and a
second opinion was sought where there was doubt. Any error in
under-reading a weak positive signal as negative would tend to
increase specificity at the expense of sensitivity; thus, the
observed low sensitivities are rather underestimations if this bias
did occur. We have also commented on the possibility of overreading of the weak signals above.
Hurly DS, et al. Sex Transm Infect 2014;90:179–184. doi:10.1136/sextrans-2013-051246
Clinical
For the male ACON tests, the voiding interval was two or
more hours rather than the first void of the morning as per the
manufacturer’s instruction, potentially slightly reducing organism load; however, this timing is unlikely to make a significant
difference to the organism load30 and hence sensitivity.
The collection order for female swabs (CRT, followed by
ACON, then NAAT) could be cause for further information bias
due to potentially decreasing loads with each swab collected,
hence overestimating the sensitivity of the POC tests at given
organism loads.
DSH, MB-S, SGB, SB, SNT and RM collaborated in writing the manuscript. DSH was
the principal investigator.
Funding This work was supported by a grant from the Secretariat of the Pacific
Community, Suva, Fiji (Grant No: 1RVUKPH01), and by funding from Fonds
Pacifique, Ministry of Foreign Affairs, French Republic and HealthLink, Auckland,
New Zealand.
Competing interests None.
Ethics approval (1) James Cook University; (2) Vanuatu Ministry of Health.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement Further information can be requested from the
corresponding author.
Utility of tests
Both tests had a high number of false-positive results, which is
of particular concern when combined with modest sensitivity. In
our CRT female population with a prevalence of 27.7%, the
positive predictive value (PPV) was 86.9%; in a population with
a prevalence of 10%, the PPV would be just 65.6%, which
would result in one in every three women receiving a falsepositive diagnosis.
The assessed sensitivity and specificity of CRT and ACON are
well below the levels stated by the manufacturers. The evaluated
tests are unlikely to be helpful in a clinical setting due to the
high proportions of false-negatives that will go untreated, as
well as false-positives that will result in overtreatment and
potential adverse social consequences.
Key messages
▸ The Chlamydia Rapid Test (CRT) and ACON tests have
performance characteristics well below those stated by the
manufacturers.
▸ Both tests are insensitive at low organism loads, and the
CRT sensitivity is related to the organism load.
▸ Better performing point-of-care tests are required for clinical
use.
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1
Anton Breinl Centre for Public Health and Tropical Medicine, School for Public
Health, Tropical Medicine and Rehabilitation Sciences, James Cook University,
Queensland, Australia
2
Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia
3
KPH Clinic, Wan Smol Bag, Port Vila, Vanuatu
4
Department of Microbiology and Infectious Diseases, The Royal Women’s Hospital,
Parkville, Victoria, Australia
5
Murdoch Childrens’ Research Institute, Parkville, Victoria, Australia
6
Department of Obstetrics and Gynaecology, University of Melbourne, Victoria,
Australia
7
Vanuatu Ministry of Health, Port Vila, Vanuatu
8
Tropical Health Solutions Pty Ltd, Townsville, Queensland, Australia
Handling editor Jackie A Cassell
Acknowledgements The authors would like to express their gratitude to the
funders the Secretariat of the Pacific Community (Suva, Fiji), the Fonds Pacifique
(Ministry of Foreign Affairs, French Republic) and HealthLink (Auckland, New
Zealand); to the Vanuatu Ministry of Health; to the nurses and staff of Wan
Smolbag and KPH Clinic, Vanuatu; to DRW for providing the training and proficiency
panels free of charge as well as technical advice about the CRT; and to Dr Rosanna
Peeling, London School of Hygiene and Tropical Medicine for reviewing the
manuscript.
Contributors All authors were involved in the design of the study and in the
revision and final approval of the manuscript to be published. DSH, SGB, SB and LT
were involved with conducting the study. MB-S conducted the statistical analysis.
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Downloaded from sti.bmj.com on April 10, 2014 - Published by group.bmj.com
Field evaluation of the CRT and ACON
chlamydia point-of-care tests in a tropical,
low-resource setting
D S Hurly, M Buhrer-Skinner, S G Badman, et al.
Sex Transm Infect 2014 90: 179-184 originally published online
December 13, 2013
doi: 10.1136/sextrans-2013-051246
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