Trends in socioeconomic inequalities in self-rated health in Germany: a time-trend analysis of repeated cross-sectional health surveys between 2003 and 2012

OBJECTIVES: This study assessed the extent of educational and income inequalities in self-rated health (SRH) in the German adult population between 2003 and 2012 and how these inequalities changed over time. DESIGN: Repeated cross-sectional health interview surveys conducted in 2003, 2009, 2010 and 2012. SETTING AND PARTICIPANTS: The study population was the German adult population aged 25–69, living in private households in Germany. In total 54 197 randomly selected participants (2003: 6890; 2009: 16 418; 2010: 17 145; 2012: 13 744) were included. MAIN OUTCOME MEASURES: SRH was assessed with one single question. Five answer categories were dichotomised into good (‘very good’ and ‘good’) versus poor (‘moderate’, ‘poor’, ‘very poor’) SRH. To estimate the extent of the correlation between absolute and relative inequalities in SRH on the one hand, and income and education on the other; slope indices of inequality (SII) and relative indices of inequality (RII) were estimated using linear probability and log-binomial regression models. RESULTS: There were considerable and persisting educational and income inequalities in SRH in every survey year. Absolute educational inequalities were largely stable (2003: SII=0.25, 95% CI 0.21 to 0.30; 2012: 0.29, 95% CI 0.25 to 0.33; p trend=0.359). Similarly, absolute income inequalities were stable (2003: SII=0.22, 95% CI 0.17 to 0.27; 2012: SII=0.26, 95% CI 0.22 to 0.30; p trend=0.168). RII by education (2003: 2.53, 95% CI 2.11 to 3.03; 2012: 2.72, 95% CI 2.36 to 3.13; p trend=0.531) and income (2003: 2.09. 95% CI 1.75 to 2.49; 2012: 2.53, 95% CI 2.19 to 2.92; p trend=0.051) were equally stable over the same period. CONCLUSIONS: We found considerable and persisting absolute and relative socioeconomic inequalities in SRH in the German adult population between 2003 and 2012, with those in lower socioeconomic position reporting poorer SRH. These findings should be a concern for both public health professionals and political decision makers.