Impact of capitation on outpatient expenses among patients with diabetes mellitus in Tianjin, China: a natural experiment

OBJECTIVES: Capitation policy, a new medical insurance settlement method implemented on 1 January 2014 in Tianjin, China, aimed to control unreasonable increases in medical costs. The goal of the current study was to evaluate the impact of capitation on outpatient expenses among patients with diabetes mellitus and provide scientific evidence for health policy-makers. DESIGN: A natural experiment. SETTING: The medical insurance database of Tianjin from 1 January 2010 to 31 December 2014. PARTICIPANTS: In total, 35 529 records were included, comprising 9646 records in the pilot group (4907 records in 2014 and 4739 records in 2013) and 25 883 records in the control group (9814 records in 2014 and 16 069 records in 2013). MAIN OUTCOME MEASURES: The outcome variables included annual total outpatient expenses, drug expenses, examination expenses, treatment expenses and other expenses. RESULTS: Capitation produced an increase in total outpatient expenses of ¥1993.76 (95% CI, ¥1643.74 to ¥2343.77) in the pilot group relative to the control group. There was also an increase in drug expenses of ¥1904.30 (95% CI, ¥1578.63 to ¥2229.96) after the implementation of capitation. An increase in examination expenses of ¥44.90 (95% CI, ¥19.11 to ¥70.68) was found in the pilot group versus the control group. Capitation also produced an increase in treatment expenses of ¥3.55 (95% CI, ¥1.01 to ¥6.09) and an increase in other expenses of ¥43.46 (95% CI, ¥26.81 to ¥60.11) in the pilot group versus the control group. CONCLUSION: Compared with those who participated in the ‘control’ policy, outpatient expenses of patients enrolled in capitation increased significantly. The increases were due to the actual needs of patients, changes in drug directories, and the autonomy and independence of hospitals. It is necessary for the government, policy-makers, hospitals, doctors, patients and supervisory agencies to improve the capitation policy.