Physician variability and uncertainty in the management of breast cancer. Results from a factorial experiment.

OBJECTIVES The purpose of this research was to determine the influence of patient and physician characteristics on physicians' level of variability and certainty in breast cancer care. METHODS One hundred twenty-eight physicians viewed a videotape of a simulated physician-patient interaction in which the patient has an "atypical" breast lump. Six patient characteristics (age, race, socioeconomic status, physical mobility, comorbidity, presentation style) were manipulated experimentally, resulting in a balanced set of 32 different "patients." Physician subjects were recruited to fill four equal strata defined by specialty (surgeons versus nonsurgeons) and experience (< or = 15 or > 15 years since graduation from medical school). RESULTS More than half of the physicians offered a diagnosis of benign breast disease, a third offered a diagnosis of breast cancer, and the rest believed that the patient had a normal breast or something "other." Results also indicated that physicians' level of certainty and test ordering behavior varied with the diagnosis that was offered. Of the six patient characteristics, only socioeconomic status influenced physician certainty; physicians were more certain of their diagnosis when the patient was of a higher socioeconomic status. Surgeons were found to be more certain of their diagnosis compared with nonsurgeons. However, surgeons were less likely to order radiologic tests or a tissue sample for metastatic evaluation than were nonsurgeons. CONCLUSIONS Overall, physicians displayed considerable variability and uncertainty when diagnosing and managing possible breast cancer.