The compliance rate for the second diagnostic evaluation after a positive fecal occult blood test: A systematic review and meta-analysis

Introduction Only a minority of patients with a positive fecal occult blood test (FOBT) undergo a follow-up second diagnostic procedure, thus minimizing its contribution for colorectal cancer (CRC) prevention. We aimed to obtain a precise estimation of this problem and also assess the diagnostic yield of CRC and adenomas by colonoscopy in these patients. Methods Literature searches were conducted for compliance OR adherence AND fecal occult blood test OR fecal immunohistochemical test AND colonoscopy. Comprehensive meta-analysis software was used. Results The search resulted in 42 studies (512,496 patients with positive FOBT), published through December 31, 2017. A funnel plot demonstrates a moderate publication bias. Compliance with any second procedure, colonoscopy, or combination of double-contrast barium enema with or without sigmoidoscopy in patients with a positive FOBT was 0.725 with 95% confidence interval (CI) 0.649-0.790 (p = 0.000), 0.804 with 95% CI 0.740-0.856 (p = 0.000) and 0.197 with 95% CI 0.096-0.361 (p = 0.000), respectively. The diagnostic yield for CRC, advanced adenoma and simple adenoma was 0.058 with 95% CI 0.050-0.068 (p = 0.000), 0.242 with 95% CI 0.188-0.306 (p = 0.000) and 0.147 with 95% CI 0.116-0.184 (p < 0.001), respectively. Discussion Compliance with diagnostic evaluation after a positive FOBT is still suboptimal. Therefore, measures to increase compliance need to be taken given the increased risk of CRC in these patients.