Interventions to Improve Follow-up of Positive Results on Fecal Blood Tests: A Systematic Review

Abstract

Background: Fecal immunochemical testing is the most commonly used method for colorectal cancer screening worldwide. However, its effectiveness is frequently undermined by failure to obtain follow-up colonoscopy after positive test results.

Purpose: To evaluate interventions to improve rates of follow-up colonoscopy for adults after a positive result on a fecal test (guaiac or immunochemical).

Data sources: English-language studies from the Cochrane Central Register of Controlled Trials, PubMed, and Embase from database inception through June 2017.

Study selection: Randomized and nonrandomized studies reporting an intervention for colonoscopy follow-up of asymptomatic adults with positive fecal test results.

Data extraction: Two reviewers independently extracted data and ranked study quality; 2 rated overall strength of evidence for each category of study type.

Data synthesis: Twenty-three studies were eligible for analysis, including 7 randomized and 16 nonrandomized studies. Three were at low risk of bias. Eleven studies described patient-level interventions (changes to invitation, provision of results or follow-up appointments, and patient navigators), 5 provider-level interventions (reminders or performance data), and 7 system-level interventions (automated referral, precolonoscopy telephone calls, patient registries, and quality improvement efforts). Moderate evidence supported patient navigators and provider reminders or performance data. Evidence for system-level interventions was low. Seventeen studies reported the proportion of test-positive patients who completed colonoscopy compared with a control population, with absolute differences of -7.4 percentage points (95% CI, -19 to 4.3 percentage points) to 25 percentage points (CI, 14 to 35 percentage points).

Limitation: More than half of studies were at high or very high risk of bias; heterogeneous study designs and characteristics precluded meta-analysis.

Conclusion: Patient navigators and giving providers reminders or performance data may help improve colonoscopy rates of asymptomatic adults with positive fecal blood test results. Current evidence about useful system-level interventions is scant and insufficient.

Primary funding source: National Cancer Institute. (PROSPERO: CRD42016048286).

Figure 1.

Flow chart of study selection for interventions to improve follow-up of positive fecal blood tests for colorectal cancer screening. CENTRAL = Cochrane Central Register of Controlled Trials.

Figure 2.

Overview of included studies of interventions to improve follow-up of positive fecal blood tests for colorectal cancer screening, by intervention level and category. HR = hazard ratio; NA = not applicable; NR = not reported. n/a: not available; UK: United Kingdom; USA: United States of America *Studies with separate reporting of more than one comparison are listed as A, B, C with further details in Table 1 †Risk of bias for individual study according to Agency for Healthcare Research and Quality and GRADE criteria (36,37), details in Appendix B ‖Follow-up interval given only when specifically provided by authors, otherwise marked unspecified ^#Adjusted absolute change, as reported by study authors