Establishing thresholds for important benefits considering the harms of screening interventions.

CONTEXT AND OBJECTIVE: Standards for clinical practice guidelines require explicit statements regarding how values and preferences influence recommendations. However, no cancer screening guideline has addressed the key question of what magnitude of benefit people require to undergo screening, given its harms and burdens. This article describes the development of a new method for guideline developers to address this key question in the absence of high-quality evidence from published literature. SUMMARY OF METHOD: The new method was developed and applied in the context of a recent BMJ Rapid Recommendation clinical practice guideline for colorectal cancer (CRC) screening. First, we presented the guideline panel with harms and burdens (derived from a systematic review) associated with the CRC screening tests under consideration. Second, each panel member completed surveys documenting their views of expected benefits on CRC incidence and mortality that people would require to accept the harms and burdens of screening. Third, the panel discussed results of the surveys and agreed on thresholds for benefits at which the majority of people would choose screening. During these three steps, the panel had no access to the actual benefits of the screening tests. In step four, the panel was presented with screening test benefits derived from a systematic review of clinical trials and microsimulation modelling. The thresholds derived through steps one to three were applied to these benefits, and directly informed the panel's recommendations. CONCLUSION: We present the development and application of a new, four-step method enabling incorporation of explicit and transparent judgements of values and preferences in a screening guideline. Guideline panels should establish their view regarding the magnitude of required benefit, given burdens and harms, before they review screening benefits and make their recommendations accordingly. Making informed screening decisions requires transparency in values and preferences judgements that our new method greatly facilitates.

How do cancer screening guidelines trade off benefits versus harms and burdens of screening? A systematic survey.

OBJECTIVES: Cancer screening guidelines differ in their recommendations for or against screening. To be able to provide explicit recommendations, guidelines need to specify thresholds for the magnitude of benefits of screening, given its harms and burdens. We evaluated how current cancer screening guidelines address the relative importance of benefits versus harms and burdens of screening. DATA SOURCE: We searched the Guidelines International Network, International Guideline Library, ECRI Institute and Medline. Two pairs of reviewers independently performed guideline selection and data abstraction. ELIGIBILITY CRITERIA: We included all cancer screening guidelines published in English between January 2014 and April 2019. RESULTS: Of 68 eligible guidelines, 25 included a statement regarding the trade-off between screening benefits versus harms and burdens (14 guidelines), or a statement of direction of the net effect (defined as benefits minus harms or burdens) (13 guidelines). None of these 25 guidelines defined how large a screening benefit should be to recommend screening, given its harms and burdens. 11 guidelines performed an economic evaluation of screening. Of these, six identified a key benefit outcome; two specified a cost-effectiveness threshold for recommending a screening option. Eight guidelines commented on people's values and preferences regarding the trade-off between benefits versus harms and burdens. CONCLUSIONS: Current cancer screening guidelines fail to specify the values and preferences underlying their recommendations. No guidelines provide a threshold at which they believe the benefits of screening outweigh its harms and burdens. PROSPERO REGISTRATION NUMBER: CRD42019138590.

Post-polypectomy colonoscopy surveillance: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2020.

The following recommendations for post-polypectomy colonoscopic surveillance apply to all patients who had one or more polyps that were completely removed during a high quality baseline colonoscopy. 1: ESGE recommends that patients with complete removal of 1 - 4 < 10 mm adenomas with low grade dysplasia, irrespective of villous components, or any serrated polyp < 10 mm without dysplasia, do not require endoscopic surveillance and should be returned to screening.Strong recommendation, moderate quality evidence.If organized screening is not available, repetition of colonoscopy 10 years after the index procedure is recommended.Strong recommendation, moderate quality evidence. 2: ESGE recommends surveillance colonoscopy after 3 years for patients with complete removal of at least 1 adenoma ≥ 10 mm or with high grade dysplasia, or ≥ 5 adenomas, or any serrated polyp ≥ 10 mm or with dysplasia. Strong recommendation, moderate quality evidence. 3: ESGE recommends a 3 - 6-month early repeat colonoscopy following piecemeal endoscopic resection of polyps ≥ 20 mm.Strong recommendation, moderate quality evidence. A first surveillance colonoscopy 12 months after the repeat colonoscopy is recommended to detect late recurrence.Strong recommendation, high quality evidence. 4: If no polyps requiring surveillance are detected at the first surveillance colonoscopy, ESGE suggests to perform a second surveillance colonoscopy after 5 years. Weak recommendation, low quality evidence.After that, if no polyps requiring surveillance are detected, patients can be returned to screening. 5: ESGE suggests that, if polyps requiring surveillance are detected at first or subsequent surveillance examinations, surveillance colonoscopy may be performed at 3 years. Weak recommendation, low quality evidence.A flowchart showing the recommended surveillance intervals is provided (Fig. 1).