This study classified participants in an incentive-based health promotion program into a high-participation group and a low-participation group using an activity-rate indicator, and examined differences and changes in health information understanding ...
This study classified participants in an incentive-based health promotion program into a high-participation group and a low-participation group using an activity-rate indicator, and examined differences and changes in health information understanding ability, stage of intention for health behavior practice, perceived adequacy of incentive level, and program satisfaction. Prior studies have largely focused on the quantitative amount of incentives or visible outcomes(e.g., weight loss, increased physical activity) and have not sufficiently evaluated long-term effects. To address this gap, the present study investigated how participants’ general characteristics, baseline health information understanding ability, baseline intention stage for health behavior practice, and participation level differentially relate to (a) program experience (perceived adequacy of incentive level and program satisfaction) and (b) program outcomes (changes in health information understanding ability and intention stage after participation). Survey data were collected from adults in their 30s to 50s, with balanced distributions by sex and age.
Analytically, independent-samples t-tests were used to assess participation-level differences by general characteristics, and participation-level differences in perceived incentive adequacy and program satisfaction were tested using t-tests and analysis of covariance (ANCOVA). Pre–post changes within each participation group and between-group differences at pre and post were examined using paired and independent-samples t-tests. In addition, between-group differences in individual change scores (Δ = post −pre) were evaluated, and hierarchical multiple regression analyses were conducted to identify predictors of change while controlling for baseline scores and general characteristics. ANCOVA was also used to assess the net effect of participation level controlling for baseline and covariates. Finally, binary logistic regression was performed to identify determinants of high- versus low-participation group membership.
Results showed that differences by general characteristics were more pronounced in the low-participation group, whereas most differences were attenuated in the high-participation group; however, education-related differences in program satisfaction remained at a trend level. Health information understanding ability was associated with baseline level and self-rated health, and participation level did not show an independent effect on change scores (Δ). In contrast, the stage of intention for health behavior practice was significantly related to participation level: between-group differences were observed in Δ-based comparisons, and this pattern persisted in hierarchical regression analyses controlling for baseline scores and general characteristics, suggesting that participation level may be an explanatory factor for changes in intention. Logistic regression indicated that baseline health information understanding ability and self-rated health were significantly associated with participation-group membership. Perceived incentive adequacy remained stable regardless of participation level, whereas program satisfaction tended to be higher in the high-participation group. Among general characteristics, self-rated health functioned as a consistent explanatory variable across multiple domains.
In summary, this study empirically identified program effects under conditions of sustained participation and demonstrated that participation level, baseline health information understanding ability, baseline intention stage, and self-rated health operate differently across domains of program experience and outcomes. To secure long-term effects, a multi-level approach is required that goes beyond incentive provision, incorporates participant characteristics and baseline profiles, strengthens active engagement, and includes differentiated program components that account for education-related differences. These findings provide important implications for future health promotion policy design.