Data source and study sample
Data came from the 2013 and 2018 National Health Services Survey (NHSS) waves in China13, 14. The NHSS is a nationally representative sample conducted every five years by the Center for Health Statistics and Information, National Health Commission of China. The NHSS covers 31 provinces/autonomous regions/ municipalities and adopts a multistage cluster random sampling method to ensure representativeness for different regions and the whole country. The NHSS is the largest comprehensive investigation of information on operational characteristics of county hospitals and PHC facilities (i.e., township health centers and village clinics) and on health status, healthcare need and demand, healthcare utilization, and financial burden of healthcare services in China. In 2013 and 2018, the NHSS sampled 156 counties with two county hospitals and five township health centers in each county, respectively. The NHSS received ethical approval from the National Statistics Bureau of China15.
In this study, we focus on a subsample of patients with chronic diseases aged 15 or older in rural areas from the 2013 and 2018 NHSS waves. People who answered yes to at least one of the following three questions were defined as having a chronic disease: 1) Have you been diagnosed hypertension? 2) Have you been diagnosed with diabetes mellitus? 3) Do you have other diagnosed chronic diseases? Rural patients were identified by hukou status (i.e., the Chinese household registration method). We excluded counties that did not match between the 2013 and 2018 waves because their status of pairing assistance cannot be identified. People under 15 years of age were excluded to reduce the heterogeneity of the sample. We also dropped observations with missing values in important variables. Finally, the study sample included 13893 and 22725 patients with chronic diseases in rural areas who lived in the sampling counties in 2013 and 2018, respectively.