Investigating Physician Bias as a Possible Explanation for Gender Disparity in the Utilization of Knee Arthroplasty Surgery

Osteoarthritis is a leading cause of long-term disability and is the most common chronic condition among women. Total knee arthroplasty (TKA) is the definitive treatment for relieving pain and improving function in individuals with moderate to severe osteoarthritis for whom medical therapy has failed. Women receive more total joint arthroplasties than men but the number of appropriate candidates willing to consider total joint arthroplasty is three times greater in women as compared to men. One potential explanation for gender disparity in access to total joint arthroplasty is that patients’ preferences for, and willingness to undergo surgery may differ by gender. Previous research has focused on the patient, and asked whether gender differences in preferences, risk aversiveness, competing comorbidities, competing responsibilities and other considerations prompt women to decline surgery to account for documented disparities in rates of use of this procedure. No study had previously examined the role of the physician in actual clinical practice. The purpose of our standardized study was to determine whether patient gender affects physicians’ decisions to refer a patient for, or to perform, TKA and the patient-physician interaction.

Seventy-one physicians (38 family physicians and 33 orthopedic surgeons) in Ontario performed blinded assessments of 2 standardized patients (1 man and 1 woman) presenting with identical clinical presentations of moderate knee osteoarthritis that differed only by gender. The standardized patients recorded the physicians’ final recommendations about TKA and elements of informed decision making present in their interaction with the physician. Four surgeons did not consent to the inclusion of their data.

Physicians were more likely to recommend total knee arthroplasty to a man than to a woman (odds ratio, 4.2; 95% CI 2.4-7.3; P‹0.001). In total, 42% of physicians recommended TKA to the man but not to the woman, and 8% of physicians recommended TKA to the woman but not to the man. Furthermore, shared decision making was more problematic for women with physicians including fewer informed decision making elements when the patient was a woman compared to a man. Physicians provided less medical information and less encouragement to participate in the decision to undergo TKA to the woman compared with the man, irrespective of their recommendation regarding TKA.

Our findings suggest that physicians may be at least partially responsible for the gender disparity in the utilization of total knee arthroplasty. Gender bias may be influencing both physicians’ clinical decision making and physicians’ interpersonal behaviour (i.e., decision-making style and patient-physician communication). This study was the first to use standardized patients to investigate the potential for physician gender bias. Using standardized patients enabled us to design a study that comes closest to controlling patients' countless clinical, social and personal characteristics, which might influence physicians' clinical decision making. We believe that this study provides the most conclusive evidence to date of a significant provider contribution to gender disparity in treatment recommendations. In addition, no study has previously addressed whether physicians are less participatory with women compared with men for patients presenting with the same chief complaint.

Investigators

CM Borkhoff, Gillian Hawker, HJ Kreder, Richard Glazier, Nizar Mahomed, JG Wright

Funding

Canadian Institutes of Health Research (CIHR)

Date

2004-2007
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. The influence of patients’ gender on physicians’ interpersonal behaviour regarding total knee arthroplasty: what if your physician doesn’t ask you to dance? Arthritis & Rheumatism (Arthritis Care & Research), in press.
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. Patients’ gender affects physicians’ treatment decisions: Physicians don’t do what they say they would do. Journal of Clinical Epidemiology, in press.
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. The effect of patients’ sex on physicians’ recommendations for total knee arthroplasty. Canadian Medical Association Journal 2008; 178:681-7.
  • Borkhoff CM, Hawker GA, Kreder HJ, Wright JG. The effect of gender on physicians’ recommendations for total knee arthroplasty. American College of Rheumatology Conference Proceedings. Arthritis & Rheum 2006; September: Abstract 1.
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. The influence of patients’ gender on physicians’ interpersonal behaviour regarding total knee arthroplasty: what if your physician doesn’t ask you to dance? Poster Presentation: Outcome Measures in Rheumatology (OMERACT), Kananaskis, Alberta, May 27-31, 2008.
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. The influence of patients’ gender on physicians’ interpersonal behaviour regarding total knee arthroplasty: what if your physician doesn’t ask you to dance? Poster Presentation: Canadian Cochrane Symposium, Edmonton, Alberta, March 6-7, 2008.
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. The influence of patients’ gender on physicians’ interpersonal behaviour regarding total knee arthroplasty: what if your physician doesn’t ask you to dance? Poster Presentation: Canadian Arthritis Network Conference, Halifax, Nova Scotia, October 12-14, 2007.
  • Borkhoff CM, Hawker GA, Kreder HJ, Glazier RH, Mahomed NN, Wright JG. The effect of gender on physicians’ recommendations for total knee arthroplasty. Poster Presentation: Canadian Orthopaedic Association Conference, Halifax, Nova Scotia, June 1-3, 2007.
  • Borkhoff CM, Hawker GA, Kreder HJ, Wright JG. The effect of gender on physicians’ recommendations for total knee arthroplasty. Poster Presentation: Canadian Arthritis Network Conference, Winnipeg, Manitoba, December 1-3, 2006.
  • Borkhoff CM, Hawker GA, Kreder HJ, Wright JG. The effect of gender on physicians’ recommendations for total knee arthroplasty. Oral Presentation: American College of Rheumatology Clinical Research Conference, Washington, DC, November 10, 2006.
  • Borkhoff CM, Hawker GA, Kreder HJ, Wright JG. The effect of gender on physicians’ recommendations for total knee arthroplasty. Poster Presentation: American College of Rheumatology Clinical Research Conference, Washington, DC, November 10, 2006.
Last modified: June 11, 2007