Effectiveness of complete diagnostic examination in clinical practice settings

Thorough follow-up of a positive fecal occult blood test (FOBT) result, or a complete diagnostic evaluation (CDE), is recommended as routine care on the basis of findings from colorectal cancer (CRC) screening trials. CDE involves either colonoscopy or the combination of flexible sigmoidoscopy and double contrast barium enema X-ray. However, little evidence outside clinical screening trial settings has been reported in the literature to support CDE performance. The focus of this study was to determine the impact of CDE in primary care practice settings.

We determined diagnostic outcomes for 461 adult patients with a positive FOBT result in 318 primary care practices in southeastern Pennsylvania and southern New Jersey. Sociodemographic data were collected and CDE status was ascertained for these patients. Polytomous logistic models were used to identify whether having CDE was associated with subsequently being diagnosed with lower gastrointestinal "neoplastic disease" or "other gastrointestinal disease" as compared to "normal findings.

Patients who underwent CDE were significantly more likely to have a reported diagnosis of colorectal neoplasia than normal findings (adjusted odds ratio = 3.65, 95% confidence interval = 1.58-8.39, p = 0.02). CDE performance did not result in the differential diagnosis of other gastrointestinal disease.

Patients with a positive screening FOBT who underwent CDE were more likely to be diagnosed with colorectal neoplasia than with less serious conditions or have normal findings. Results support the use of CDE in CRC screening.