Background Healthcare reforms in many countries have shown a movement from pure payment systems to mixed payment systems. However, there remains an insufficient understanding of how to design better mixed payment systems and how such systems, especially Diagnosis-Related-Group (DRG)-based systems, benefit patients. We therefore designed a controlled laboratory experiment to investigate the effects of fee-for-service (FFS), DRG, and mixed payment systems on physicians’ service provision. Methods A total of 210 medical students were recruited from Capital Medical University as subjects. They, in the role of physicians, were randomly divided into seven groups and chose the quantity of medical services for different patient types under pure FFS, pure DRG, or mixed payment schemes that included two FFS-based mixed payment schemes and three DRG-based mixed payment schemes. There were five rounds of each group of experiments, and each subject made 18 decisions per round. The quantity of medical services provided by subjects were collected. And relevant statistics were computed and analyzed by nonparametric tests and random effects model. Results The results showed that the physicians’ overprovision (underprovision) of services under FFS (DRG) schemes decreased under mixed payment schemes, resulting in higher benefit to patients under mixed payment schemes. Patients’ health conditions also affected physicians’ behavior but in different directions. Higher disease severity was associated with higher deviation of physicians’ quantity choices from the optimal quantity under DRG and DRG-based mixed payment schemes, while the opposite was found for FFS and FFS-based mixed payment schemes. Conclusions Mixed payment systems are a better way to balance physicians’ profit and patients’ benefit. The design of mixed payment systems should be adjusted according to the patient’s health conditions. When patients are in lower disease severity and resource consumption is relatively small, prospective payments or mixed systems based on prospective payments are more suitable. While for patients in higher disease severity, retrospective payments or mixed systems based predominantly on retrospective payments are better.

Background Rational allocation of human resources for health is crucial for ensuring public welfare and equitable access to health services. Understanding medical students’ job preferences could help develop effective strategies for the recruitment and retention of the health workforce. Most studies explore the relationship between extrinsic incentives and job choices through discrete choice experiments (DCEs). Little attention has been paid to the influence of intrinsic altruism on job choice. This study aimed to explore the heterogeneous preferences of medical students with different levels of altruism regarding extrinsic job attributes. Methods We conducted an online survey with 925 medical students from six hospitals in Beijing from July to September 2021. The survey combined job-choice scenarios through DCEs and a simulation of a laboratory experiment on medical decision-making behavior. Behavioral data were used to quantify altruism levels by estimating altruistic parameters based on a utility function. We fit mixed logit models to estimate the effects of altruism on job preference. Results All attribute levels had the expected effect on job preferences, among which monthly income (importance weight was 30.46%, 95% CI 29.25%-31.67%) and work location (importance weight was 22.39%, 95% CI 21.14%–23.64%) were the most salient factors. The mean altruistic parameter was 0.84 (s.d. 0.19), indicating that medical students’ altruism was generally high. The subgroup analysis showed that individuals with higher altruism levels had a greater preference for non-financial incentives such as an excellent work environment, sufficient training and career development opportunities, and a light workload. The change in the rate of the uptake of a rural position by individuals with lower levels of altruism is sensitive to changes in financial incentives. Conclusions Medical students’ altruism was generally high, and those with higher altruism paid more attention to non-financial incentives. This suggests that policymakers and hospital managers should further focus on nonfinancial incentives to better motivate altruistic physicians, in addition to appropriate economic incentive when designing recruitment and retention interventions. Medical school administrations could attach importance to the promotion of altruistic values in medical education.

Background Mixed payment schemes have become one of the effective measures to balance medical costs and quality of medical services. However, altruism as an intrinsic motivation may influence the effect of switching from a pure payment system to mixed payment schemes. This study aimed to quantify physicians’ altruism and analyze the effect of changes of payment system on physicians’ altruism and thus proposed references for the reform of payment system. Methods We simulated an exogenous payment system in a controlled laboratory with five experimental groups and 150 medical student subjects. Physicians’ altruism was measured by estimating altruistic parameter and marginal rate of substitution. The non-parametric test and the least square regression analysis were used to analyze the differences of altruistic parameters between pure payment systems and mixed payment schemes. Finally, we analyzed the effect of changes in payment system accompanied by changes in trade-off range on physicians’ altruism. Results We find that the mean value of individual altruistic parameter is 0.78 and the marginal rate of substitution is 1.078. Their estimates at the individual level were significantly positively correlated (Spearman’s ρ = 0.715, p < 0.01). The shift from pure payment system to mixed payment scheme reduced the altruistic parameter. However, the altruistic parameter increased with the increase of the trade-off range. Physicians who were more altruistic generated higher patients’ health benefit. For each unit increase in altruistic parameter, the increase in patients’ health benefit was lower in mixed payment scheme than in the pure payment system. Conclusion The estimates of altruistic parameters are reliable. Physicians attach a higher weight to patients’ benefit than to their own profit. Mixed payment schemes improve physicians’ behavior and relate to lower altruistic parameters; physicians only need to sacrifice less personal profits to generate the same or even higher altruistic parameter as under the pure payment system. The design of mixed payment schemes that make the interests of physicians and patients close to each other by reducing the trade-off range can provide implication for the reform of payment system in which the physicians’ interest and the patients’ benefit are consistent.