Changes in preventive care utilisation and its influencing factors among Chinese adults before and after the healthcare reform: cross-sectional evidence from the China Health and Nutrition Survey in 2004-2015

China launched its health reform in 2009. This study aimed to assess changes in preventive care utilisation (PCU) and its relationship with the healthcare reform. A cross-sectional study using demographic characteristics, socioeconomic status, environmental factors, and lifestyle and health status data of adults from five waves (2004-2015) of the China Health and Nutrition Survey (CHNS) was conducted. Multilevel mixed-effects logistic regression models were used. Data were derived from urban and rural communities of nine provinces in China. Data were obtained from five waves of the CHNS, with 9960 participants in 2004, 9888 in 2006, 10 286 in 2009, 9709 in 2011, and 10 628 in 2015. The primary outcome was PCU. PCU in 2004-2015 among adults was 3.29%, 3.13%, 3.77%, 4.95% and 2.73%, respectively. Whether before or after the health reform, having a history of disease and female gender were positive influencing factors of PCU. Before 2009, PCU was significantly associated with gender, income, medical insurance status and region. Age, medical insurance status, history of drinking and education level significantly affected PCU in 2009-2011. Having medical insurance was no longer a positive influencing factor of PCU, while high income had a negative effect on PCU, in 2011-2015. PCU from 2004 to 2015 was low and the health reform in China may lack sustainable effect on PCU. Further studies on how to ensure sustainability of PCU are necessary, and further reforms on preventive care services should be aimed at different ages, rural areas and participants without history of disease.