Use of the dye stain assay and ultraviolet light test for assessing vaginal insertion of placebo-filled applicators before and after sex.
BACKGROUND
Applicator dye staining and ultraviolet (UV) light have been used in trials to measure adherence, but not in the setting of before and after sex gel dosing (BAT-24). This study was designed to determine if semen or presex gel dosing impacts the sensitivity and specificity of a dye stain assay (DSA) for measuring vaginal insertion of placebo-filled applicators with BAT-24 dosing.


METHODS
Healthy monogamous couples received Microlax-type applicators (Tectubes, Åstorp, Sweden) filled with hydroxyethylcelluose placebo gel. Women were instructed to vaginally insert 1 dose of gel before and a second dose after sex and to return applicators within 48 hours after sex. Applicators were stained to detect semen, followed by UV then DSA, and scored by 2 readers. Positive and negative controls were randomly included in applicator batches.


RESULTS
Fifteen couples completed the study. Each woman returned at least 6 applicators over a 30-day period. The sensitivity for insertion of postsex applicators was higher for UV (97%) compared with DSA (90%), and the specificity was similar (≥96%). For presex applicators, the sensitivity and specificity were higher for DSA (100%) compared with UV testing (87% sensitivity, 96% specificity). Among returned postsex applicators, 95% tested positive by UV compared with 87% by DSA. Agreement between readers was significantly better on the presex applicators for DSA than for UV, and for postsex readings, agreement was less than half that for UV, although the results were not statistically significant.


CONCLUSIONS
Applicator tests are feasible for measuring adherence in trials with gel dosing before and after sex.
From the *Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY; †The Population Council, New York, NY; ‡Albert Einstein Cancer Center, Bronx, NY; and §National Cancer Institute, National Institutes of Health, Bethesda, MD.
Marla J
MJ
Keller
Niall
N
Buckley
Lauren L
LL
Katzen
Jennifer
J
Walsh
Barbara
B
Friedland
Sarah
S
Littlefield
Juan
J
Lin
Xiaonan
X
Xue
Terri
T
Cornelison
Betsy C
BC
Herold
Mark H
MH
Einstein
D000282:Administration, Intravaginal; D000328:Adult; D003075:Coitus; D004396:Coloring Agents; D016503:Drug Delivery Systems / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D057566:Self Report; D012661:Semen; D012680:Sensitivity and Specificity; D013997:Time Factors; D014466:Ultraviolet Rays
D004396:Coloring Agents