Why doctors do what they do: determinants of physician behavior.

Direct payments to physicians account for about 20% of the medical care dollar, but physician decisions cause over 80% of the costs of medical care. Decision making can be viewed in a number of ways: as pure information processing, as an interaction with various stimuli, including financial penalties and incentives, and as social behavior, interacting with and reacting to peer and leadership influence. The model that accounts for the greatest amount of the available data is a multifactorial one that takes all of these views into account. The most successful behavior change efforts use a variety of mutually reinforcing approaches, and must be present constantly or behaviors revert to highly variable (lower quality) actions and decisions. This appears to be a behavioral version of the second law of thermodynamics (entropy increases spontaneously). The best practice model to manage costs and quality appears to be one in which physicians and administrators have adequate up to date information available, make group decisions, develop and continuously improve agreed upon methods of practice, interact and think before acting, and have rewards for such behavior.