Social inequalities in self-rated health in Sweden using the Population Health Performance Index: a cross-sectional study

Sweden faces challenges in improving average health and reducing health inequalities simultaneously. Traditional research methods often measure these aspects separately, posing a dilemma for policymakers. Thus, the Population Health Performance Index (PHPI) has been proposed as a summary measure that integrates both aspects. This study aimed to determine the PHPI for self-rated health (SRH) by income and education in Sweden across its 21 regions. Data were obtained from the 2021 Health on Equal Terms survey, a population-based cross-sectional study from Sweden. This survey included 17 538 participants aged 16-84 years. The outcome was poor SRH, stratified by the highest and lowest education and income groups. The PHPI was calculated as a weighted average of the mean and inequality index according to a neutral inequality aversion weight of 0.5. The prevalence of poor SRH was 28.7%, with pronounced disparities between high- and low-income/education groups. Overall, the PHPI by income and educational inequality was closer to zero across regions, albeit small relative differences were observed among the regions compared. The index also revealed substantial spatial disparities between Sweden's northern and southern regions. The PHPI can be a complementary tool for policymakers to monitor social inequalities in health. The findings call for targeted interventions to address socioeconomic and regional disparities to achieve equity in health in Sweden.