Testing Makes Us Stronger HIV Testing Campaign for Black Gay and Bisexual Men in the United States: An Interrupted Time Series Evaluation

Theoretical Background and research questions/hypothesis: Black gay, bisexual, and other men who have sex with men (BMSM) are the subpopulation most disproportionately affected by HIV in the United States. Testing Makes Us Stronger (TMUS), a communication campaign designed to increase HIV testing rates among BMSM aged 18-44 years, was implemented at the local level in six cities in the United States from December 2011 through September 2015. To determine whether the campaign was associated with changes in HIV testing levels among the priority audience, we used interrupted time series analysis (ITSA) to test whether HIV testing among BMSM aged 18-44 in TMUS implementation cities significantly increased after the launch of the campaign.

Methods: We conducted secondary analysis of monthly city-level HIV testing event data from eleven months prior to the campaign launch (January 2011) through the end of Year 3 of the campaign (December 2014) (the latest date that surveillance data was available for). We used ITSA to compare pre- and post-campaign trends in the number of monthly HIV testing events among the priority audience in six of the campaign’s implementation cities during that time period.

Results: In the 11 months prior to the launch of TMUS, HIV testing events among BMSM in the six campaign implementation cities decreased by a rate of nearly 35 tests per month (p =.021). After the introduction of TMUS, the number of HIV testing events among BMSM in the same cities increased by more than six tests per month (p = .002). Therefore, there is evidence of a reversal from the pre-campaign downward trend in HIV testing events following the launch of the TMUS campaign. In an effort to demonstrate that the observed increase in HIV testing was not likely attributable to other events occurring during our study period, we ran the same model using monthly HIV testing-event data from BMSM aged 18–44 in U.S. cities where the TMUS campaign had not been implemented at the local level. Based on this analysis, we found no evidence of a post-campaign change in HIV testing levels or trends among BMSM 18-44 in the nonimplementation cities, p =.571. Given this, we can be more confident that the post-campaign change that we observed in HIV testing event rates in the implementation cities was not caused by some other factor affecting BMSM nationally or testing rates in general.

Conclusions: The results of the ITSA suggest that the TMUS campaign was effective at increasing HIV testing among BMSM ages 18-44 years in the six TMUS implementation cities over and above underlying trends. This study represents one of the few evaluations that have used accepted, rigorous time-series analysis procedures to assess a health communication campaign.

Implications for research and/or practice: ITSA represents a quasi-experimental technique for investigating campaign effects beyond underlying time trends when serial outcome data are available. Future evaluations can be further strengthened by incorporating a comparison group to account for the effects of history and maturation on pre- and post-campaign trends.