Measuring and predicting surgeons' practice styles for breast cancer treatment in older women.

BACKGROUND Few measures exist to assess physicians' practice style, and there are few data on physicians' practice styles and patterns of care. OBJECTIVES To use clinical vignettes to measure surgeons' "propensity" for local treatments for early-stage breast cancer and to describe factors associated with propensity. RESEARCH DESIGN AND SUBJECTS A cross-sectional mailed survey with telephone follow-up of a random sample of 1,000 surgeons treating Medicare beneficiaries in fee-for-service settings. MEASURES Outcome measures include treatment propensity, self-reported practice, and actual treatment received by the surgeons' patients. RESULTS Propensities were significantly associated with actual treatment, controlling for covariates. Area Medicare fees were the strongest predictor of propensity, followed by region, attitudes, volume, and gender. For instance, after other factors were considered, surgeons practicing in areas with the highest breast-conserving surgery (BCS) fees were 8.61 (95% CI 2.26-32.73) times more likely to have a BCS propensity than surgeons in areas with the lowest fees. Surgeons with the strongest beliefs in patient participation in treatment decisions were nearly 6 times (95% CI 1.67-20.84) more likely to have a BCS propensity than surgeons with the lowest such beliefs, controlling for covariates. Male surgeons were also independently more likely to have a mastectomy propensity than female surgeons. CONCLUSIONS Surgeons' propensities explain some of the observed variations in breast cancer treatment patterns among older women. Standardized scenarios provide a practical method to measure practice style and could be used to evaluate physician contributions to shared decision making, practice patterns, costs and outcomes, and adherence to guidelines.