The enabling effect of social support on vaccination uptake via self-efficacy and planning

Purpose: In the context of worksite influenza vaccination programmes, social support, action planning and perceived self-efficacy were examined as predictors of participation. Mechanisms among these predictors were analysed by applying the enabling effect model to vaccination. Moreover, this model was extended by the inclusion of planning. Methods: In a large German company, a survey on influenza vaccination was launched with 200 employees taking part in the five-month follow-up. Using regression procedures, a sequential mediation model was examined, leading from social support via self-efficacy and planning to vaccination behaviour. Results: The three predictors jointly accounted for 47% of the vaccination participation variance. The enabling effect model was confirmed, highlighting how social support may promote self-efficacy beliefs. Further analysis yielded the extended model, revealing planning as a mediator between self-efficacy and subsequent behaviour while the indirect path from social support via self-efficacy to behaviour remained. Conclusions: Multiple step mediation analysis underscored the relevance of social support and self-efficacy. It also revealed planning as a proximal factor that may facilitate participation in a worksite influenza vaccination programme.