Systematic Review With Meta-analysis

The Appropriateness of Colonoscopy Increases the Probability of Relevant Findings and Cancer While Reducing Unnecessary Exams

Leonardo Frazzoni; Marina La Marca; Franco Radaelli; Cristiano Spada; Liboria Laterza; Rocco Maurizio Zagari; Franco Bazzoli; Cesare Hassan; Marzio Frazzoni; Mario Dinis-Ribeiro; Lorenzo Fuccio


Aliment Pharmacol Ther. 2020;53(1):22-3. 

In This Article

Abstract and Introduction


Background: Colonoscopy is frequently performed in industrialised countries. Inappropriate colonoscopies might lead to unnecessary exams, increasing risks and costs.

Aim: To estimate the impact of colonoscopy appropriateness in terms of gain in additional diagnoses and sparing of unnecessary exams.

Methods: Systematic review including studies reporting the prevalence of relevant findings, colorectal cancer (CRC) and inflammatory bowel disease (IBD) according to colonoscopy appropriateness as defined by the American Society for Gastrointestinal Endoscopy and European Panel on Appropriateness of Gastrointestinal Endoscopy.

Results: Twenty-one studies with 19,822 patients were included. Colonoscopy was appropriate in 15,162 (71%, CI 64%–78%). Appropriateness significantly increased the probability of relevant findings (34% vs. 18%; RR 1.81, CI 1.53–2.14), CRC (7% vs. 2%; RR 3.62, CI 2.44–5.37) and IBD (6% vs. 4%; RR 1.86, CI 1.09–3.19). Appropriateness had sensitivity 88% (CI 85%–91%), 97% (CI 93%–98%) and 89% (CI 80%–94%), and specificity 24% (CI 20%–29%), 22% (CI 18%–26%) and 24% (CI 20%–28%) for relevant findings, CRC and IBD, respectively. On average, performing colonoscopy with appropriate indication would find 15 (CI 10–21) more relevant findings, five (CI 3–9) more CRCs and three (CI 1–9) more diagnoses of IBD per 100 patients, and save 24 (CI 20–29), 22 (CI 18–26) and 24 (CI 20–28) examinations per 100 patients for relevant findings, CRC and IBD, respectively.

Conclusions: Appropriateness affects the diagnostic yield of colonoscopy for CRC, IBD and relevant findings. Appropriateness criteria are useful, although integrated with clinical evaluation of the patient.


Colonoscopy is among the most frequent of endoscopic examinations performed in industrialised countries.[1] Colonoscopy requires a considerable amount of resources, in terms of costs and workload for endoscopic services and overall burden for the health care systems.[2] This is especially true in the context of the current SARS-CoV-2 pandemic, in which endoscopic services cannot address the usual workload and have to undergo a thorough reorganisation.[3]

The appropriateness of health care procedures is a fundamental parameter for assessing the quality of a health service.[4] The indication for a procedure is appropriate when the expected benefits are greater than the potential risks for the patient (risk/benefit analysis) and costs (cost/benefit analysis). The benefits of colonoscopy comprehend the prevention of colorectal cancer (CRC) through early diagnosis and removal of pre-cancerous lesions, and the diagnosis of clinically relevant lesions (eg sources of bleeding, inflammatory bowel disease), while the risks lie in the invasiveness of the procedure. The European Society of Gastrointestinal Endoscopy (ESGE) recommends that at least 85% of colonoscopies should have an appropriate indication.[5] However, real-life data showed that this goal is not always reached. US data showed that up to 60% of physicians did not follow the recommended intervals for follow-up in the CRC screening program.[6] In line with this view, in order to reduce the burden of inappropriate exams, ESGE has recently provided a position paper with recommendations for endoscopic findings which do not deserve any endoscopic follow-up.[7]

Indications to colonoscopy are heterogeneous, and have been systematised through the years according to the European Panel for Appropriateness in Gastrointestinal Endoscopy (EPAGE)[8,9] and American Society for Gastrointestinal Endoscopy (ASGE)[10,11] criteria. These criteria define clinical scenarios which deserve further investigation with colonoscopy. A prior meta-analysis published in 2011 demonstrated that performing colonoscopy with appropriate indication had suboptimal results in terms of diagnostic performance.[12] However, since then numerous studies have been published, and quality parameters for colonoscopy have been issued,[5] thus the estimates might well have changed. Applying standardised criteria for prescribing colonoscopy should be a priority in a free-access system, especially in a setting of resources constraints.

Aims of this systematic review and meta-analysis were to estimate the rate of appropriate colonoscopies, the prevalence of relevant findings and CRC overall and according to appropriateness, and its impact in terms of gain in additional diagnoses and sparing of unnecessary examinations.