Effectiveness and cost-effectiveness of the Salut Programme: a universal health promotion intervention for parents and children—protocol of a register-based retrospective observational study

INTRODUCTION: There is inadequate evidence for the effectiveness and cost-effectiveness of health promotion interventions. The Salut Programme aims to reach all parents and children in the Västerbotten County of Sweden with a combination of health promotion interventions initiated during pregnancy and continued over the childhood period. This study protocol describes an effectiveness study and an economic evaluation study, where the ongoing Salut Programme is compared to care-as-usual over the periods of pregnancy, delivery and the child's first 2 years of life. METHODS: A register-based retrospective observational study design will be used with existing data sources with respect to exposures and outcomes. Outcomes of interest are clustered at 3 points: around the child's birth, 1 month after the child's birth and 2 years after the child's birth. We will simulate an experiment by retrospectively identifying and comparing children and their parents in the geographical areas where the Salut Programme was implemented since 2006 and onwards, and the areas where the Programme was not implemented before 2009. Outcomes will be analysed and compared for the premeasure period, and the postmeasure period for both groups. Our analysis combines difference-in-difference estimation with matching. A complementary analysis will be carried out on the longitudinal subsample of mothers who gave birth at least once during each of the time periods. The economic evaluation aims to capture the wider societal costs and benefits of the Salut Programme for the first 2 years of the children's lives. Incremental costs will be compared with incremental health gains and the results will be presented as a cost-consequence analysis. ETHICS AND DISSEMINATION: The Regional Ethical Review Board in Umeå has given clearance for the Salut Programme research (2010-63-31M). No individual's identity will be revealed when presenting results. This study will provide information that can guide decision-makers to allocate resources optimally.