Effectiveness of the VOICES/VOCES sexually transmitted disease/human immunodeficiency virus prevention intervention when administered by health department staff: does it work in the "real world"?

Background: Prevention providers wonder whether benefits achieved in the original, researcher-led, efficacy trials of interventions are replicated when the intervention is delivered in real-world settings by their agency's staff.

Methods: A replication study was conducted at 2 public sexually transmitted disease (STD) clinics (New York City and San Juan, PR). Using a controlled trial design, intervention (VOICES/VOCES) and comparison conditions (regular clinic services) were assigned in alternating 4-week blocks. Trained agency staff delivered the intervention. Effectiveness was assessed for incident STDs, redemption of coupons for condoms at neighborhood location after the visit, and improved knowledge and attitudes about STDs and condoms.

Results: A total of 3365 patients were recruited, completed the protocol, and followed through STD surveillance systems for an average of 17 months. Of 397 with an incident infection, 226 (13.4%) were among those enrolled during comparison blocks; 171 were among those in the intervention condition (10.2%). Controlling for site and gender, participants enrolled during intervention blocks were significantly less likely to have an incident STD reported to the surveillance system (hazard ratio, 0.78; 95% confidence interval, 0.64-0.96). Intervention block participants scored higher on scales of STD knowledge (4.89 vs. 3.87, P < 0.001) and condom knowledge, attitude, and efficacy (10.98 vs. 9.16, P < 0.001). More of those exposed to VOICES/VOCES redeemed condoms (P < 0.05). Positive effects were more consistent in New York, which may be related to fidelity of implementation.

Conclusions: A packaged human immunodeficiency virus prevention intervention can be delivered by agencies, with benefits similar to those achieved in the research setting.