The Association of Physician Attitudes about Uncertainty and Risk Taking with Resource Use in a Medicare HMO

Abstract

Purpose. To explore the association between the attitudes of primary care physicians toward uncertainty and risk taking, as measured by a validated survey, with resource use in a Medicare HMO. Design. All primary-care internists (n = 20) in a large, multi- specialty clinic were surveyed to measure their attitudes about uncertainty and risk taking using three previously developed scales. Results were linked with administrative data for 792 consecutive patients in a recently created Medicare HMO. The patients' index visits occurred between April 1, 1995, and November 30, 1995. Analysis. Charges stemming from several claim types (primary care and subspecialty physician, laboratory, radiology, and ambulatory procedures) in the 30 days following the index visit were summed. The physician scales were dichotomized at the median to seek unadjusted associations with charges. Generalized estimation equations were used to account for the correlation of charges resulting from patients' being nested within phy sicians and adjusted for physician characteristics (age, sex, years in practice) and patient characteristics (age, sex, comorbidity). Main results. The physician response rate was 90%. Most physicians (90%) were male. The mean age of the patients was 74 years, and 69% were female. The mean cost (±SD) per patient was $621.61 ± 1,737.31. From the unadjusted analysis, high "anxiety due to uncertainty" was asso ciated with higher patient charges ($197.85 vs $158.21, p = 0.01). From the multivar iable analysis, each standard deviation increase in "anxiety due to uncertainty" (3.5 points) corresponded to a 17% increase in mean charges (p < 0.01) and each similar increase in "reluctance to disclose uncertainty to patients" (1.92 points) corresponded to a 12% increase (p = 0.03). However, increasing "reluctance to disclose mistakes to physicians" and increasing physician risk-taking propensity were associated with decreased total charges [-10% per standard deviation (1.34 points), p = 0.02, and -8% per standard deviation (3.26 points), p = 0.02, respectively]. Conclusion. Physi cian attitudes toward uncertainty were significantly associated with patient charges. Further investigation may improve prediction of patient-care charges, offer insight into the medical decision-making process, and perhaps clarify the relationship between cost, uncertainty, and quality of care. Key words: physician uncertainty; risk taking; managed care; medical charges. (Med Decis Making 1998;18:320-329)