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What predicts non-retention in microbicide trials?
Paul J Feldblum1, Vera Halpern, Che-Chin Lie
1FHI, Research Triangle Park, NC 27709, USA. pfeldblum@fhi.org
Contemporary Clinical Trials
|March 9, 2011
Summary
Younger, less educated women were less likely to complete HIV prevention trials. Identifying and supporting these participants can improve study validity and efficiency in microbicide research.
Area of Science:
- Clinical Trials
- HIV Prevention
- Microbicides
Background:
- High loss to follow-up in HIV prevention trials can compromise study power and introduce bias.
- Identifying factors associated with participant non-retention is crucial for improving trial efficiency and validity, especially in developing countries.
Purpose of the Study:
- To summarize retention rates in four sub-Saharan African microbicide trials.
- To evaluate baseline factors associated with non-retention among women participating in these trials.
Main Methods:
- Analysis of data from 7,086 women across four trials of two candidate vaginal microbicides (C31G and cellulose sulfate).
- Cox regression modeling was used to identify factors associated with participant non-retention, defined as loss to follow-up or early discontinuation before HIV infection.
Main Results:
- Overall non-retention rate was 21.4% (1,514 participants).
- Factors significantly associated with non-retention included younger age (HR=0.95), less education (HR=0.97), condom use at last sex (HR=1.18), higher frequency of sex acts (HR=1.01), and presence of baseline candidiasis or bacterial vaginosis (HR=1.12).
Conclusions:
- Younger and less educated women exhibited lower retention rates in these microbicide trials.
- These demographic factors may also be associated with increased HIV infection risk, highlighting the need for targeted retention strategies.
- Enhanced retention efforts focused on high-risk individuals can optimize the efficiency and validity of HIV prevention studies.
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