COMPARISONS OF PRIMARY CARE PHYSICIANS' INITIALLY PREFERRED COLORECTAL CANCER SCREENING STRATEGIES WITH THOSE DERIVED FROM A MULTI-CRITERIA ANALYSIS

Purpose: Implementation of current colorectal cancer screening involves a choice among several recommended screening options with differing advantages and disadvantages. Through a multi-criteria analysis, we compared physicians’ preferred screening strategies with those most consistent with their interpretation of clinical evidence, priorities, and preferences.
Methods: After a brief review of current guidelines, 41 primary care physicians indicated their preferred colorectal cancer screening approach for an average risk, healthy 50 year old patient and then completed a multi-criteria analysis using the Analytic Hierarchy Process (AHP).  The AHP analysis included the following considerations: effectiveness in preventing cancer, risk of serious screening-related side effects (perforation or major bleeding), false positive rates, screening frequency, screening test preparation, and the nature of the screening test. The analysis assumed regular screening through age 80 using the same strategy. Age-specific data or descriptions for each currently recommended screening option were presented in a blinded fashion except for the descriptions of the procedures. We assessed the reliability of the AHP results using the consistency ratio, a measure of the internal consistency of the judgments made during the analysis.
Results: The mean age of the study physicians was 44.7 years; 63% were male. Thirty-five (85%) indicated that colonoscopy every 10 years was their preferred strategy. Four (10%) preferred annual fecal occult blood tests (fobt) and colonoscopy every 10 years, 1 (2%) preferred annual fobt, and 1 (2%) preferred flexible sigmoidoscopy every 5 years. The preferred and AHP-based screening strategies differed for 15 (37%) of the 41 physicians and 10 (28%) of the 37 who preferred one of the currently recommended screening strategies. Most of the differences were due to 7 physicians who preferred colonoscopy whose AHP-analysis identified flexible sigmoidoscopy as the best choice. The overall mean consistency ratio was 0.067; 39 physicians (95%) had ratios in the acceptable range (< 0.20).
Conclusion: Many primary care physicians’ usual preferences regarding colorectal cancer screening may not accurately reflect their clinical judgment and priorities. If confirmed, these results suggest that physicians have difficulty in assimilating complex evidence involving multiple domains and that the regular use of multiple criteria decision techniques could help physicians better align their practice patterns with the clinical evidence and their personal priorities and preferences.