Reaching out to promote physical activity in Australia: a statewide randomized controlled trial of a stage-targeted intervention

Purpose. This study examined the broader use of a print-media intervention, which was previously shown to be effective at promoting physical activity to participants recruited from a regional Australian community, as a strategy suitable for a more diverse statewide population sample. Methods. Participants were randomly selected adults who responded to a telephone interview conducted by the New South Wales Health Department and consented to Participate in a randomized controlled trial. Consenters were allocated to either intervention (n = 361) or control (n = 358) conditions. The intervention, a personalized letter plus stage-targeted booklets, was sent 1 week postbaseline. Data were collected via telephone interview at baseline and 2 and 8 months and were analyzed using repeated measures analysis of variance (ANOVA) and mean squared statistics. Results. The groups were similar at baseline (mean age 43 +/- 3 years; 64 % women). Process evaluation showed high intervention recall (76 % at 2 months) and high follow-up response rates (> 85 % at 8 months) were achieved. Nonsignificant increases in physical activity were observed (Fl,719 = 2.18, p = .14). Discussion. A single mailing of stage-targeted print materials was not effective in promoting increases in physical activity among participants selected from the statewide population. Future research could examine how the effectiveness of print media might be enhanced, possibly by using supplementary media, community-based prompts, or other incentives.