Mediators of physical activity behavior change: a multivariate approach.

摘要: Using a multivariate extension of the Baron and Kenny (1986) mediation framework, we examined simultaneous effect psychosocial variables hypothesized to mediate relationship between motivationally-tailored physical activity intervention, 6-month behavior in 239 healthy, under-active adults (mean age=47.5; 82% women). Participants were randomly assigned 1) Print-based feedback; 2) Telephone-based or 3) Contact Control. All criteria satisfied for both intervention arms. In terms size, moderate indirect Print (0.39, 95% CI=0.21, 0.57) was due increases behavioral processes (0.54, CI= 0.29, 0.80) being attenuated by decreases cognitive (-0.17, 95%CI= -0.31,-.03). A observed Telephone (0.47, CI=0.28, 0.66), with (0.61, CI=0.34, 0.87) (0.15, CI=-0.27, -0.02); self-efficacy decisional balance mediational paths did not attain statistical significance. These findings highlight importance studies that deconstruct theoretical components interventions determine which combination produces greatest changes at lowest cost.