Efficacy and Mediation of a Theory-Based Physical Activity Intervention for African American Men Who Have Sex with Men: A Randomized Controlled Trial

Abstract

Background: Few trials have tested physical-activity interventions among sexual minorities, including African American men who have sex with men (MSM).

Purpose: We examined the efficacy and mediation of the Being Responsible for Ourselves (BRO) physical-activity intervention among African American MSM.

Method: African American MSM were randomized to the physical-activity intervention consisting of three 90-min one-on-one sessions or an attention-matched control intervention and completed pre-intervention, immediately post-intervention, and 6- and 12-month post-intervention audio computer-based surveys.

Results: Of the 595 participants, 503 completed the 12-month follow-up. Generalized estimating equation models revealed that the intervention increased self-reported physical activity compared with the control intervention, adjusted for pre-intervention physical activity. Mediation analyses suggested that the intervention increased reasoned action approach variables, subjective norm and self-efficacy, increasing intention immediately post-intervention, which increased physical activity during the follow-up period.

Conclusions: Interventions targeting reasoned action approach variables may contribute to efforts to increase African American MSM's physical activity.

Clinical trial registration: The trial was registered with the ClinicalTrials.gov Identifier NCT02561286 .

Keywords: African American men; Intervention study; Mediation analysis; Men who have sex with men; Physical activity; Reasoned action approach.

Conflict of interest statement

COI and Ethical Adherence: None of the authors has a conflict of interest regarding the research reported in this manuscript. The manuscript represents valid work and neither this manuscript nor one with substantially similar content has ben published or is being considered for publication elsewhere. The research reported in this manuscript was approved by the Institutional Review Board #8 of the University of Pennsylvania, Philadelphia, PA. Written informed consent from the men was required for the participation in this trial.

Figures

Figure 1. Flow Diagram of Participants through Trial

Figure 2. Structural Equation Model of the Effect of the Intervention on Theoretical Constructs and Weighted Average Physical Activity, African American Men, Philadelphia, PA 2008-2011

Note. Estimates are unstandardized indices: CFI=0.960, TLI=0.921, 0.0 Efficacy and Mediation coefficients (95% ACI) from ordinary least square regressions (bootstrap=2000). Goodness, RMSEA = 0.047 (90% CI: 0.037, 0.057), chi-square=101.136 (DF=29, P=0.000) 33 Goodness-of-Fit 0.000), SRMR=0.064