Sandra M. Coulon, Dawn K. Wilson, Sarah Griffin, Sara M. St. George, Kassandra A. Alia, Nevelyn N. Trumpeter, Abraham K. Wandersman, Melinda Forthofer, Shamika Robinson, Barney Gadson

Evaluating programs targeting physical activity may help to reduce disparate rates of obesity among African Americans. We report formative process evaluation methods and implementation dose, fidelity, and reach in the Positive Action for Today's Health trial. We applied evaluation methods based on an ecological framework in 2 community-based police-patrolled walking programs targeting access and safety in underserved African American communities. One program also targeted social connectedness and motivation to walk using a social marketing approach. Process data were systematically collected from baseline to 12 months. Adequate implementation dose was achieved, with fidelity achieved but less stable in both programs. Monthly walkers increased to 424 in the walking-plus-social marketing program, indicating expanding program reach, in contrast to no increase in the walking-only program. Increased reach was correlated with peer-led Pride Strides (r = .92; P < .001), a key social marketing component, and program social interaction was the primary reason for which walkers reported participating. Formative process evaluation demonstrated that the walking programs were effectively implemented and that social marketing increased walking and perceived social connectedness in African American communities.