Who benefits from quality competition in health care? A theory and a laboratory experiment on the relevance of patient characteristics.

We study how competition between physicians affects the provision of medical care. In our theoretical model, physicians are faced with a heterogeneous patient population, in which patients systematically vary with regard to both their responsiveness to the provided quality of care and their state of health. We test the behavioral predictions derived from this model in a controlled laboratory experiment. In line with the model, we observe that competition significantly improves patient benefits as long as patients are able to respond to the quality provided. For those patients, who are not able to choose a physician, competition even decreases the patient benefit compared to a situation without competition. This decrease is in contrast to our theoretical prediction implying no change in benefits for passive patients. Deviations from patient-optimal treatment are highest for passive patients in need of a low quantity of medical services. With repetition, both, the positive effects of competition for active patients as well as the negative effects of competition for passive patients become more pronounced. Our results imply that competition can not only improve but also worsen patient outcome and that patients' responsiveness to quality is decisive.

The effects of competition on medical service provision.

We explore how competition between physicians affects medical service provision. Previous research has shown that, without competition, physicians deviate from patient-optimal treatment under payment systems like capitation and fee-for-service. Although competition might reduce these distortions, physicians usually interact with each other repeatedly over time and only a fraction of patients switches providers at all. Both patterns might prevent competition to work in the desired direction. To analyze the behavioral effects of competition, we develop a theoretical benchmark that is then tested in a controlled laboratory experiment. Experimental conditions vary physician payment and patient characteristics. Real patients benefit from provision decisions made in the experiment. Our results reveal that, in line with the theoretical prediction, introducing competition can reduce overprovision and underprovision, respectively. The observed effects depend on patient characteristics and the payment system, though. Tacit collusion is observed and particularly pronounced with fee-for-service payment, but it appears to be less frequent than in related experimental research on price competition.

Sorting into payment schemes and medical treatment: A laboratory experiment.

In this study, we introduce the opportunity for physicians to sort into capitation or fee-for-service payment. Using a controlled medically framed laboratory experiment with a sequential within-subject design allows isolating sorting from incentive effects. We observe a strong preference for fee-for-service payment, which does not depend on subjects' prior experience with one of the two payment schemes. Further, we identify a significant sorting effect. Subjects choosing capitation deviate ex ante less from patient-optimal medical treatment than subjects who sort into fee-for-service payment. Particularly the latter become even less patient-oriented after introducing the choice option. Consequently, the opportunity to choose between fee-for-service and capitation payment worsens patient treatment, if at all. Our results hold for medical and for nonmedical students.

The Effects of Introducing Mixed Payment Systems for Physicians: Experimental Evidence.

Mixed payment systems have become a prominent alternative to paying physicians through fee-for-service and capitation. While theory shows mixed payment systems to be superior, causal effects on physicians' behavior when introducing mixed systems are not well understood empirically. We systematically analyze the influence of fee-for-service, capitation, and mixed payment systems on physicians' service provision. In a controlled laboratory setting, we implement an exogenous variation of the payment method. Medical and non-medical students in the role of physicians in the lab (N = 213) choose quantities of medical services affecting patients' health outside the lab. Behavioral data reveal significant overprovision of medical services under fee-for-service and significant underprovision under capitation, although less than predicted when assuming profit maximization. Introducing mixed payment systems significantly reduces deviations from patient-optimal treatment. Although medical students tend to be more patient regarding, our results hold for both medical and non-medical students. Responses to incentive systems can be explained by a behavioral model capturing individual altruism. In particular, we find support that altruism plays a role in service provision and can partially mitigate agency problems, but altruism is heterogeneous in the population. Copyright © 2015 John Wiley & Sons, Ltd.

A new look at physicians' responses to financial incentives: Quality of care, practice characteristics, and motivations.

There is considerable controversy about what causes (in)effectiveness of physician performance pay in improving the quality of care. Using a behavioral experiment with German primary-care physicians, we study the incentive effect of performance pay on service provision and quality of care. To explore whether variations in quality are based on the incentive scheme and the interplay with physicians' real-world profit orientation and patient-regarding motivations, we link administrative data on practice characteristics and survey data on physicians' attitudes with experimental data. We find that, under performance pay, quality increases by about 7pp compared to baseline capitation. While the effect increases with the severity of illness, the bonus level does not significantly affect the quality of care. Data linkage indicates that primary-care physicians in high-profit practices provide a lower quality of care. Physicians' other-regarding motivations and attitudes are significant drivers of high treatment quality.

Rewards for information provision in patient referrals: A theoretical model and an experimental test.

We study whether bonus payments for information provision can improve the information flow between physicians. A primary care physician (PCP) decides on the provision of information of varying qualities to a specialist while referring a patient. Our theoretical model, which includes altruism and loss aversion, predicts that bonus payments increase the provision of both high- and low-quality information. Running a controlled laboratory experiment we find support for this prediction. If the beneficiary of information provision receives a higher payoff than the PCP, we observe that PCPs more often pass on high-quality information when the beneficiary is a patient. If the beneficiary receives a lower payoff than the PCP, the type of the beneficiary (specialist or patient) does not affect the provision of high-quality information.

The dynamics of behavior in modified dictator games.

We investigate the dynamics of individual pro-social behavior over time. The dynamics are tested by running the same experiment with the same subjects at several points in time. To exclude learning and reputation building, we employ non-strategic decision tasks and a sequential prisoners-dilemma as a control treatment. In the first wave, pro-social concerns explain a high share of individual decisions. Pro-social decisions decrease over time, however. In the final wave, most decisions can be accounted for by assuming pure selfishness. Stable behavior in the sense that subjects stick to their decisions over time is observed predominantly for purely selfish subjects. We offer two explanation for our results: diminishing experimenter demand effects and moral self-licensing.