Implementation fidelity of the 'Stay One Step Ahead' home safety intervention: a mixed-methods analysis.

Objective: To assess implementation fidelity of the Stay One Step Ahead (SOSA), a complex intervention which was delivered by health visiting teams, children's centres, and family mentors and was aimed at preventing unintentional home injuries in children under 5 in disadvantaged communities.

Study Design: A mixed-methods evaluation of the implementation fidelity of the SOSA intervention.

Methods: A conceptual framework for implementation fidelity was used to triangulate data from questionnaires and semistructured interviews with parents and practitioners, observations of parent and practitioner contacts, and meeting documents. Quantitative data were analysed using logistic regression and descriptive statistics. Thematic analysis was used for qualitative data.

Results: Parents in intervention wards were more likely to receive home safety advice from a practitioner than those living in matched control wards. Monthly safety messages and family mentor home safety activities were delivered with greater fidelity than other intervention components. Content most frequently adapted included the home safety checklist used by health visiting teams, and safety weeks delivered at children's centres.

Conclusion: Consistent with similarly complex interventions, SOSA was delivered with variable fidelity in a challenging environment. The findings add to the body of evidence on implementation fidelity of home injury prevention programmes, providing important information for future intervention development and delivery.