Background: Primary care physicians (PCPs) exhibit widely varying referral rates, resulting in dramatic differences in the exposure of their patients to specialists. The relationships between this physician behavior and costs and patient outcomes are unknown.
Objectives: To examine the relationships between PCP referral rates and costs, risk of avoidable hospitalization, health status, and satisfaction.
Design: Cross-sectional analyses of claims and patient survey data.
Setting and subjects: Independent practice association (IPA)-style managed care organization in the Rochester, NY, metropolitan area. The 1995 claims data included 457 PCPs in the IPA and 217,606 adult patients assigned to their panels. Approximately 50 consecutive patients of each of a random sample of 100 PCPs completed a patient survey in 1997-1998.
Measures: From the claims data, total expenditures per panel member, the risk of avoidable hospitalization, and physician referral rate were measured. Measures derived from the survey included SF-12 scores, satisfaction, and physician referral rate.
Results: The relationship between physician referral rate and per-panel-member costs was not statistically significant after case-mix adjustment of the referral rate. There was no relationship between the case-mix-adjusted referral rate and risk of avoidable hospitalization. In the survey data, there was no adjusted relationship between the physicians' referral rate and their patients' self-rated physical or mental health. There was a modest direct relationship between patient satisfaction and survey-derived referral rate.
Conclusions: Despite stable, wide variations in PCP referral rates, there are few discemible relationships between this physician behavior and costs and patient outcomes. Efforts to constrain PCP referrals to specialists may be misguided.