Prostate-specific antigen to ascertain reliability of self-reported coital exposure to semen.
OBJECTIVE
The objective of this study was to assess the validity of women's reports of recent unprotected sex by testing for prostate-specific antigen (PSA) in vaginal samples.


METHODS
The authors conducted prospective research with 332 female sex workers attending 2 public dispensaries in Madagascar.


RESULTS
Among women who reported no sex or protected sex only within the past 48 hours, 21% and 39%, respectively, tested positive for PSA. Among those testing positive for PSA, no differences in PSA concentrations were found among those reporting no sex, protected sex only, or at least one unprotected act.


CONCLUSIONS
The substantial disagreement between self-reports and measurement of a biologic marker of semen exposure in vaginal specimens substantiates that self-reports of sexual behavior cannot be assumed to be valid measures. Future sexually transmitted infection/HIV and pregnancy prevention studies should confirm the validity of self-reports or use end points that do not rely on self-reported data.
Gallo
Maria F
MF
Family Health International (FHI), Research Triangle Park, North Carolina, USA. mgallo@cdc.gov
Behets
Frieda M
FM
Steiner
Markus J
MJ
Hobbs
Marcia M
MM
Hoke
Theresa Hatzell
TH
Van Damme
Kathleen
K
Ralimamonjy
Louisette
L
Raharimalala
Leonardine
L
Cohen
Myron S
MS
D003075:Coitus; D017280:Condoms / Q000706:statistics & numerical data; D003625:Data Collection / Q000592:standards*; D005260:Female; D006801:Humans; D008270:Madagascar / Q000453:epidemiology; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D012661:Semen / Q000378:metabolism*; D011477:Sex Work; D012749:Sexually Transmitted Diseases / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D011795:Surveys and Questionnaires; D047568:Unsafe Sex / Q000706:statistics & numerical data*; D014626:Vaginal Smears
D017430:Prostate-Specific Antigen