Risk Aversion and Costs A Comparison of Family Physicians and General Internists

,

Original Research

Risk Aversion and Costs A Comparison of Family Physicians and General Internists

J Fam Pract. 2000 January;49(1):12-17

By

Kevin Fiscella, MD, MPH

References

1. Cherkin DC, Rosenblatt RA, Hart LG, Schneeweiss R, LoGerfo J. The use of medical resources by residency-trained family physicians and general internists: is there a difference? Med Care. 1987;25:455-69.

2. Noren J, Frazier T, Altman I, DeLozier J. Ambulatory medical care: a comparison of internists and family-general practitioners. N Engl J Med 1980;302:11-6.

3. Greenfield S, Nelson EC, Zubkoff M, et al. Variations in resource utilization among medical specialties and systems of care: results from the medical outcomes study. JAMA 1992;267:1624-30.

4. Bertakis KD, Helms J, Azari R, Callahan EJ, Robbins JA, Miller J. Differences between family physicians’ and general internists’ medical charges. Med Care 1999;37:78-82.

5. Scherger JE, Gordon MJ, Phillips TJ, LoGerfo JP. Comparison of diagnostic methods of family practice and internal medicine residents. J Fam Pract 1980;10:95-101.

6. Bennett MD, Applegate WB, Chilton LA, Skipper BJ, White RE. Comparison of family medicine and internal medicine: charges for continuing ambulatory care. Med Care 1983;21:830-9.

7. Linn LS, Yager J, Leake BD, Gastaldo G, Palkowski C. Differences in the numbers and costs of tests ordered by internists, family physicians, and psychiatrists. Inquiry 1984;21:266-75.

8. Franks P, Dickinson JC. Comparisons of family physicians and internists: process and outcome in adult patients at a community hospital. Med Care 1986;24:941-8.

9. Julnes TE, Baker TA. Family practice and internal medicine office fees: an analysis of charge differences. J Fam Pract 1993;37:35-43.

10. Franks P, Clancy CM. Referrals of adult patients from primary care: demographic disparities and their relationship to HMO insurance. J Fam Pract 1997;45:47-53.

11. Smith DH, McWhinney IR. Comparison of the diagnostic methods of family physicians and internists. J Med Educ 1975;50:264-70.

12. Conry CM, Pace WD, Main DS. Practice style differences between family physicians and internists. J Am Board Fam Pract 1991;4:399-406.

13. Zeldow PB, Daugherty SR. Personality profiles and specialty choices of students from two medical school classes. Acad Med 1991;66:283-7.

14. Geller G, Tambor ES, Chase GA, Hofman KJ, Faden RR, Holtzman NA. Incorporation of genetics in primary care practice: will physicians do the counseling and will they be directive? Arch Fam Med. 1993;2:1119-25.

15. Grol R, Whitfield M, De Maeseneer J, Mokkink H. Attitudes to risk taking in medical decision making among British, Dutch and Belgian general practitioners. Br J Gen Pract 1990;40:134-6.

16. Zaat JOM, van Eijk JTM. General practitioners’ uncertainty, risk preference, and use of laboratory tests. Med Care 1992;30:846-54.

17. Pearson SD, Goldman L, Orav EJ, et al. Triage decisions for emergency department patients with chest pain: do physicians’ risk attitudes make the difference? J Gen Intern Med 1995;10:557-64.

18. Allison JJ, Kiefe CI, Cook EF, Gerrity MS, Orav EJ, Centor R. The association of physician attitudes about uncertainty and risk taking with resource use in a Medicare HMO. Med Decis Making 1998;18:320-9.

19. Linn LS, Yager J, Cope D, Leake B. Health status, job satisfaction, job stress, and life satisfaction among academic and clinical faculty. JAMA 1986;254:2775-82.

20. Gerrity MS, DeVellis RF, Earp JA. Physicians’ reactions to uncertainty in patient care: a new measure and new insights. Med Care 1990;28:724-36.

21. Gerrity M, White K. Physicians’ reactions to uncertainty: refining the constructs and scales. Motivat Emotion 1995;19:175-91.

22. Ashworth CD, Williamson PR, Montano D. A scale to measure physician beliefs about psychosocial aspects of patient care. Soc Sci Med 1984;19:1235-8.

23. Levinson W, Roter D. Physicians’ psychosocial beliefs correlate with their patient communication skills. J Gen Intern Med 1995;10:375-9.

24. Ryan RM, Connell JP. Perceived locus of causality and internalization: examining reasons for acting in two domains. J Personality Soc Psychology 1989;57:749-61.

25. Williams GC, Deci EL. Internalization of biopsychosocial values by medical students: a test of self-determination theory. J Personality Soc Psychology 1996;70:767-79.

26. Williams GC, Wiener MW, Markakis KM, Reeve J, Deci EL. Medical students’ motivation for internal medicine. J Gen Intern Med 1994;9:327-33.

27. Williams GC, Deci EL. The importance of supporting autonomy in medical education. Ann Intern Med 1998;129:303-8.

28. Duan N, Manning W, Morris CN, et al. A comparison of alternative models for the demand for medical care. J Business Econ Stat 1983;1:115-26.

29. Weiner JP, Starfield BH, Steinwachs DM, Mumford LM. Development and application of a population-oriented measure of ambulatory care case-mix. Med Care 1991;29:452-72.

30. Duan N. Smearing estimate: a nonparametric retransformation method. J Am Stat Assoc 1983;78:605-10.

31. Stephens GG. Family medicine as counterculture: 1979. Fam Med 1998;30:629-36.

32. Saultz JW. Reflections on internal medicine and family medicine. Ann Intern Med 1996;124:600-3.

33. Engel GL. The biopsychosocial model and family medicine. J Fam Pract 1983;16:409, 412-3.

34. Engel GL. The biopsychosocial model and medical education. N Engl J Med 1982;13:802-5.

BACKGROUND: The authors of previous studies have suggested that family physicians generate lower health care expenditures than internists. Explanations for this difference have not been explored.

METHODS: We surveyed 61 family physicians and 112 internists within a managed care organization regarding their demographic, practice, and psychological characteristics. We derived physician costs per enrollee and case-mix adjustment using claims data.

RESULTS: In a multivariate analysis, we found that family physicians were significantly less risk averse than general internists. After adjustment for case mix, family physicians generated 5% lower costs (95% confidence interval [CI], 2% -9%). After adjustment for case mix, risk averse physicians generated higher expenditures; a one standard deviation increase in risk-aversion was associated with a 3% increase in expenditures (95% CI, 1% - 5%). After adjustment for case mix and risk aversion, family physicians’ costs were no longer significantly lower (3%; 95% CI, -1% to 7%). None of the other physician demographic, practice, or psychological characteristics were significantly associated with case-mix-adjusted expenditures.

CONCLUSIONS: The lower costs per patient generated by family physicians compared with internists may reflect psychological differences in risk aversion.

Many^1-5 studies (though not all^6-8) show that family physicians generate lower patient costs than internists. Family physicians have been reported to spend less time per patient,² order fewer laboratory tests,^1,2 charge less,⁹ refer patients less frequently to consultants,^1,3,10 and generate lower hospital¹ and overall costs.³ These findings have been replicated with residents^1,5 and practicing physicians,^2-5 using written patient scenarios,^5,11 in national samples,^1,2,10,12 after adjustment for differences in rates of morbidity (case mix),^1,3,9,10 and recently in a randomized trial.⁴

The reasons for these interspecialty differences in costs are not clear. However, research on physician attributes suggests potential explanations. The personality profile of medical students planning to go into family medicine shows a higher tolerance for ambiguity or uncertainty,¹³ which has been found to be inversely related to the likelihood of referral for genetic counseling.¹⁴ A related construct, risk aversion (a general avoidance of risk taking in life), has been linked to greater use of diagnostic testing and referrals^15,16 and greater likelihood of hospitalization for chest pain.¹⁷ Physicians participating in a Medicare health maintenance organization who reported less anxiety about uncertainty or who were less risk averse generated lower patient charges.¹⁸

For our study, we hypothesized that less anxiety generated by uncertainty and less risk aversion would explain differences in expenditures generated by family physicians and general internists.¹⁸ We used data from a panel of family physicians and internists in a local managed care organization (MCO) to explore these hypotheses.

Methods

Sample

We conducted our investigation in the Rochester, NY, metropolitan area using the claims database of the largest local MCO. Approximately 500,000 people (more than 50% of the local population) were enrolled in the MCO. It employed an independent practitioner association model in which the primary care physicians and the specialists were not capitated. Each patient was assigned to a primary care physician, and more than 95% of those physicians participated in the independent practitioner model. Our patient study sample included adults enrolled in the MCO who were aged 25 years or older and were assigned to a primary care physician (457 family physicians and internists) during 1995 or 1996. To facilitate comparisons between the 2 specialties, visits to obstetrician/gynecologists or for obstetric and gynecologic problems were excluded. Our final sample was made up of approximately 243,000 adult patients of whom 210,000 were active in the system during the year. We derived information on physician specialty, age, and sex from a database maintained by the independent practitioner association.

Physician Survey

Physicians were offered a $50 honorarium to encourage participation in a mailed survey. The 10-minute survey was sent to primary care physicians (internists and family physicians) in the independent practitioner association who had at least 100 patients in the MCO in both 1995 and 1996 (n = 274). There were survey responses from 182 physicians. Questionnaire survey data on all sampled physicians included demographics (age and sex), practice characteristics, specialty (family practice or internal medicine), years in practice (current site or any site), practice intensity (sessions and patients per week), and group size (number of partners). The questionnaire also included several psychometric scales, each with a 5- to 7-choice Likert-type response alternative. The scales were selected on the basis of the evidence of their reliability and their relationship to physician behavior. Physician satisfaction was measured using a scale developed by Linn and colleagues.¹⁹ The original 13-item scale was augmented with 3 additional questions about satisfaction with managed care (Cronbach’s a = 0.87 in this sample). Physicians’ anxiety generated by uncertainty was assessed with 3 items selected from the scales developed by Gerrity and coworkers^20,21 to measure physicians’ reactions to uncertainty. The scale includes items like: “The uncertainty of patient care often troubles me” and “I usually feel anxious when I am not sure of a diagnosis” (Cronbach’s a = 0.76). Attitude toward risk in general (risk aversion) was assessed using a 6-item scale developed by Pearson and colleagues¹⁷ that was found to predict the likelihood of physicians admitting patients with chest pain. The scale includes items such as: “I enjoy taking risks”; “I consider security an important element in every aspect of my life”; and “I try to avoid situations that have uncertain outcomes” (Cronbach’s a = 0.84). A 6-item scale to measure malpractice concerns was developed by one of the authors (GCW). Its items included, “Sometimes I ask for consultant opinions primarily to reduce my risk of being sued” and “Relying on clinical judgment rather than on technology to make a diagnosis is becoming riskier from a medicolegal perspective” (Cronbach’s a = 0.84). An 8-item version of the Physician Psychosocial Belief Scale²² was included. The questions included: “I do not focus on psychosocial problems until I have ruled out organic disease” and “Patients will reject the idea of my dealing with psychosocial issues” (Cronbach’s a = 0.84). Levinson and Roter²³ found that physicians’ scores on this scale correlated with their communication behaviors during audiotaped encounters. Two scales developed by one of the authors (GCW) assessed the extent to which the physician’s motivation for ordering tests or referring to specialists is controlled (7 items) and autonomous (4 items). Each item started with the stem “The reasons I order diagnostic tests or refer my patients to specialists are…” and included possible answers such as: “… because my reputation is at stake with each decision I make” and “…because my patients would be upset if I didn’t” to indicate controlled motivation and “…because it helps me fully understand what is causing my patients’ problem” and “because it’s in my patients’ best interests” to show autonomous motivation. (Cronbach’s a = 0.83 for the controlled scale and 0.82 for the autonomous scale).* The validity and reliability of these scales and constructs have been demonstrated in previous studies.^24-27