Do “behavior modification” strategies aimed at motivating gay men to reduce their risk of contracting STDs work better than a slogan and a smile? Last year, the venerable venereal wonk John Imrie, MD, of London’s Royal Free and University College Medical School, designed a test to compare the two. The votes are in, so hang on to your swinging chads.

In the study, 343 gay guys who had either an STD or unsafe sex in the past year sat through a 20-minute counseling session. Half then attended an intensive daylong intervention, while the control group went home.

A year later, the “modified” men reported a decrease in condomless anal sex (from 37 percent of the group to 27 percent), while the controls reported a slight increase (from 30 to 32 percent). So far, so good. But wait! The mods also had a much higher rate of new STD infections than the controls: 58 vs. 43 percent.

The explanation for this strange statistical disconnect may be as simple as intervention vets’ feeling obliged to report success—less unsafe sex than last year. Does the study confirm anything else but the fact that people lie about sex? Try this: “Even carefully formulated behavioral interventions,” Imrie’s team told The British Medical Journal, “should not be assumed to bring benefit.”

As the battles over HIV and other STD prevention funding get increasingly partisan and nasty, look for this study to hit big in local and national meetings.