Background:
STD/HIV behavioral risk assessments provide the basis for clinic-based prevention counseling. Time constraints in the STD clinic setting may limit the ability of clinicians to conduct detailed and complex risk behavioral interviews with their patients.

Objective:
To examine the discriminatory value of two different brief approaches to questioning on condom use in the STD/HIV clinical risk assessment in STD clinics in Baltimore, Maryland.

Method:
This was a records-based historical cohort study. We examined electronic data captured from the standardized medical evaluation for persons seen in two STD clinics during 2004-2005. Clinicians recorded every individual patient's report of condom use in two different ways: as a graded proportional estimate (always/often/sometimes/never) for all sexual encounters, as well as condom use at the last sexual encounter (“critical incident”). We used the outcome of urogenital GC as the surrogate indicator of STD/HIV risk. We used multivariate logistic regression to adjust for age, gender, known GC exposure, and number of sex partners.

Result:
Records from 20,602 clients (58% men, 42% women) from 2004-2005 were available for analysis. Report of proportional condom use (always/often/sometimes/never) did not reliably predict risk of GC after adjustment for age, gender, known GC exposure, and number of sex partners. However, report of condom use at last sexual encounter did independently predict decreased risk of urogenital GC infection (OR 0.76, 95%CI: 0.59-0.99; p=0.042).

Conclusion:
Reported use of condoms during the last sexual encounter reliably discriminates STD/HIV risk among STD clinic patients.

Implications:
The critical incident approach focusing on the last sexual encounter should be considered to be a useful component of the brief risk assessment in the STD clinic setting.