Reasons patients with a positive fecal occult blood test result do not undergo complete diagnostic evaluation

Screening for fecal occult blood reduces colorectal cancer mortality by identifying patients with positive results for complete diagnostic evaluation (CDE). CDE rates are suboptimal, however. We sought to determine common reasons for nonperformance of a CDE as recorded by the primary care physician.

We undertook a descriptive analysis of reasons reported by physicians for nonperformance of CDE in a nested sample of patients with positive fecal occult blood test (FOBT) results from a randomized controlled trial designed to evaluate the impact of a physician intervention (CDE reminder-feedback and educational outreach) on recommendation and performance rates in primary care practices. Inspection of administrative data for 1,468 patients with positive results showed that 661 (45%) did not undergo CDE. We reviewed patient follow-up forms, which were completed by physicians for patients who did not have a CDE, to identify reasons for nonperformance.

Nonperformance of CDE was due to physician decision for 217 patients (33%). In 123 patients (19%), reasons for nonperformance were compatible with the guidelines, and in 94 patients (14%), they were not. Reasons wholly or partially due to factors other than physician decision were noted in 212 patients (32%); physician action was considered to be appropriate in these patients. For the 232 patients (35%) without a clearly documented reason for CDE nonperformance, the appropriateness of the physicians' action could not be determined.

Decision making by primary care physicians had a major effect on nonperformance of CDE after a positive FOBT result. Colorectal cancer screening programs should include guidance for physicians about when a CDE should and should not be performed.