Physician referral rates: style without much substance?

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.

Do physicians who diagnose more mental health disorders generate lower health care costs?

BACKGROUND: Underrecognition and undertreatment of mental health disorders in primary care have been associated with poor health outcomes and increased health care costs, but little is known about the impact of the diagnoses of mental health disorders on health care expenditures or outcomes. Our goal was to examine the relationships between the proportion of mental health diagnoses by primary care physicians and both health care expenditures and the risk of avoidable hospitalizations. METHODS: We used cross-sectional analyses of claims data from an independent practice association-style (IPA) managed care organization in Rochester, New York, in 1995. The sample was made up of the 457 primary care physicians in the IPA and the 243,000 adult patients assigned to their panels. We looked at total expenditures per panel member per year generated by each primary care physician and avoidable hospitalizations among their patients. RESULTS: After adjustment for case mix, physicians who recorded a greater proportion of mental health diagnoses generated significantly lower per panel member expenditures. For physicians in the highest quartile of recording mental health diagnoses, expenditures were 9% lower than those of physicians in the lowest quartile (95% confidence interval, 5% - 13%). There was a trend (P = .051) for patients of physicians in the highest quartile of recording mental health diagnoses to be at lower risk for an avoidable hospitalization than those of physicians in the lowest quartile. CONCLUSIONS: Primary care physicians with higher proportions of recorded mental health diagnoses generate significantly lower panel member costs, and their patients may be less likely to be admitted for avoidable hospitalization conditions.

Why do physicians vary so widely in their referral rates?

OBJECTIVE: To determine which physician practice and psychological factors contribute to observed variation in primary care physicians' referral rates. DESIGN: Cross-sectional questionnaire-based survey and analysis of claims database. SETTING: A large managed care organization in the Rochester, NY, metropolitan area. PARTICIPANTS: Internists and family physicians. MEASUREMENTS AND MAIN RESULTS: Patient referral status (referred or not) was derived from the 1995 claims database of the managed care organization. The claims data were also used to generate a predicted risk of referral based on patient age, gender, and case mix. A physician survey completed by a sample of 182 of the physicians (66% of those eligible) included items on their practice and validated psychological scales on anxiety from uncertainty, risk aversiveness, fear of malpractice, satisfaction with practice, autonomous and controlled motivation for referrals and test ordering, and psycho-social beliefs. The relation between the risk of referral and the physician practice and psychological factors was examined using logistic regression. After adjustment for predicted risk of referral (case mix), patients were more likely to be referred if their physician was female, had more years in practice, was an internist, and used a narrower range of diagnoses (a higher Herfindahl index, also derived from the claims data). Of the psychological factors, only greater psychosocial orientation and malpractice fear was associated with greater likelihood of referral. When the physician practice factors were excluded from the analysis, risk aversion was positively associated with referral likelihood. CONCLUSIONS: Most of the explainable variation in referral likelihood was accounted for by patient and physician practice factors like case mix, physician gender, years in practice, specialty, and the Herfindahl index. Relatively little variation was explained by any of the examined physician psychological factors.

Variations in primary care physician referral rates.

OBJECTIVE: To examine primary care physician referral rate variations, including their extent and their stability over time and across diagnostic categories. DATA SOURCES: 1995/1996 claims data for adult patients from a large Independent Practitioner Association (IPA) model managed care organization (MCO) in the Rochester, NY metropolitan area. The IPA includes over 95 percent of area primary care physicians (PCPs), and the MCO includes over 50 percent area residents. STUDY DESIGN: Referral rates (patients referred to and seen by specialists one or more times/patients seen by PCP/year) were developed for the PCPs (457 general practitioners, family physicians, and internists) in the MCO, including observed referral rates, expected referral rates based on case-mix adjustment across the whole sample, physician-specific case mix-adjusted referral rates (empirical Bayes estimates), and diagnostic category-specific case mix-adjusted referral rates. PRINCIPAL FINDINGS: Wide variations in observed referral rates (0.01-0.69 patients referred/patients seen/year) were attenuated relatively little by case-mix adjustment and persisted in case mix-adjusted empirical Bayes estimates (0.02-0.65). The year-to-year case mix-adjusted referral rate correlation was .90. Correlations of case mix adjusted-referral rates across diagnostic categories were moderate (r=.46-.67). CONCLUSIONS: PCP referral rates exhibit wide variations that are independent of case mix, remain stable over time, and are generalizable across diagnostic categories. Understanding this physician practice variation and its relationship to costs and outcomes is critical to evaluating the effect of current efforts to reduce PCP referral rates.