Plain English Summary
Background and study aims
Chlamydia is a common sexually transmitted infection. The current guidelines recommend testing again after a chlamydia infection, but the best timing is not known. The aim of this study is to find the best time to retest after chlamydia treatment.
Who can participate?
Heterosexual patients of the Amsterdam STI clinic with a chlamydia infection, aged 12 or older
What does the study involve?
After being diagnosed and treated, participants are randomly allocated to be offered a retest either 8, 16 or 26 weeks later. Participants can choose to do this at home and send a self-collected sample by mail, or at the clinic. The number and percentage of participants retested and chlamydia infection rates are assessed up to 35 weeks later.
What are the possible benefits and risks of participating?
The benefit for the participant is that chlamydia re-infections are diagnosed and treated. There are no risks involved in participation.
Where is the study run from?
Public Health Service (GGD) Amsterdam (Netherlands)
When is the study starting and how long is it expected to run for?
May 2012 to April 2017
Who is funding the study?
Public Health Service (GGD) Amsterdam (Netherlands)
Who is the main contact?
Prof. Henry de Vries
Study website
Contact information
Type
Scientific
Contact name
Prof Henry de Vries
ORCID ID
http://orcid.org/0000-0001-9784-547X
Contact details
Public Health Service
Department of Infectious Diseases
Nieuwe Achtergracht 100
Amsterdam
1018WT
Netherlands
Additional identifiers
EudraCT/CTIS number
IRAS number
ClinicalTrials.gov number
Protocol/serial number
-
Study information
Scientific title
What is the optimal time to retest patients with a urogenital chlamydia infection? A randomized controlled trial
Acronym
Study hypothesis
The trialists postulated that in heterosexual visitors of the STI clinic with a urogenital chlamydia infection, the proportion being retested would be lower with a later timing of retest, and that the proportion positive would be higher with a later timing of retest. If so, the trialists envisioned an optimum timing to offer a retest, which would provide the highest yield of diagnosed reinfections.
Ethics approval(s)
The study was reviewed by the ethics committee of the Academic Medical Center, University of Amsterdam, Netherlands. The board exempted the study from a full review and written patient consent as it was a modification of current practice and did not apply to the Dutch law ‘Medical Research Involving Human Subjects Act (WMO)’.
Study design
Single-centre randomized controlled trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Study setting(s)
Other
Study type
Screening
Patient information sheet
No participant information sheet available
Condition
Urogenital Chlamydia trachomatis infection
Intervention
A single-centre randomized controlled trial among urogenital chlamydia nucleic acid amplification test positive heterosexual Amsterdam STI clinic clients. After treatment, patients were randomly assigned for retesting 8, 16 or 26 weeks later. Patients could choose to do this at home (and send a self-collected sample by mail), or at the clinic. Retest uptake and chlamydia positivity at follow-up were calculated.
Intervention type
Other
Primary outcome measure
1. The number and percentage of participants retested up to 35 weeks after inclusion
2. The proportion of participants who were CT positive, measured by nucleic acid amplification test, up to 35 weeks after inclusion
Secondary outcome measures
1. The number, percentage and chlamydia positivity proportion of participants who:
1.1. Returned more than 1 week before the assigned date
1.2. Returned at assigned date (this was defined as a visit in the period >1 week before, until 6 weeks after the assigned date)
1.3. Returned >6 weeks after the assigned date but no later than 35 weeks (8 months) after inclusion
1.4. Those who did not return within 35 weeks of inclusion
Overall study start date
01/05/2012
Overall study end date
01/04/2017
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Heterosexual patients of the Amsterdam STI clinic testing positive for urogenital chlamydia
2. Aged 12 years or older
Participant type(s)
Patient
Age group
Mixed
Sex
Both
Target number of participants
2500
Participant exclusion criteria
Does not meet inclusion criteria
Recruitment start date
01/05/2012
Recruitment end date
01/03/2013
Locations
Countries of recruitment
Netherlands
Study participating centre
Public Health Service (GGD) Amsterdam
STI outpatient clinic
Department of Infectious Diseases
Weesperplein 1
Amsterdam
1018 WT
Netherlands
Sponsor information
Organisation
Public Health Service
Sponsor details
Department of Infectious Diseases
Nieuwe Achtergracht 100
Amsterdam
1018 WT
Netherlands
Sponsor type
Government
Website
ROR
Funders
Funder type
Government
Funder name
Public Health Service (GGD) Amsterdam
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
The trialists have presented the preliminary results during two scientific meetings, in 2013 during the international society for STD Research (ISSTDR) meeting in Vienna, Austria, and in 2014 during the International Society for Human Chlamydia Infection (ISHCI) meeting in Monterrey, CA, USA. Currently they are submitting the definite results to a scientific peer reviewed journal.
Intention to publish date
15/05/2017
Individual participant data (IPD) sharing plan
The datasets generated during and/or analysed during the current study are/will be available upon request from Prof. Henry de Vries.
IPD sharing plan summary
Available on request
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Results article | results | 01/02/2018 | Yes | No |