Performance and evaluation in computed tomographic colonography screening: protocol for a cluster randomised trial

Background: Colorectal cancer (CRC) is a common, important healthcare priority and improving patient outcome relies on early diagnosis. Colonoscopy and computed tomographic colonography (CTC) are commonly-used diagnostic tests. Although colonoscopists are highly regulated and must be accredited, no analogous process exists for CTC. There are currently no universally accepted radiologist performance indicators for CTC, and lack of regulatory oversight may lead to variability in quality and lower neoplasia detection rates. This study aims to determine whether a structured educational training and feedback programme can improve radiologist interpretation accuracy. / Methods: NHS England CTC reporting radiologists will be cluster randomised to either an intervention (one-day individualised training and assessment with feedback) or control (assessment with no training or feedback) arm. Each cluster represents radiologists reporting CTC in a single NHS site. Both the intervention and control arm will undertake four CTC assessments at baseline, 1-month (after training; intervention arm or enrolment; control arm), 6- and 12 months to assess their detection of colorectal cancer (CRC) and 6mm+ polyps. The primary outcome will be difference in sensitivity at the 1-month test between arms. Secondary outcomes will include sensitivity at 6 and 12 months and radiologist characteristics associated with improved performance. Multilevel logistic regression will be used to analyse per-polyp and per-case sensitivity. Local ethical and Health Research Authority approval have been obtained. / Discussion: Lack of infrastructure to ensure that CTC radiologists can report adequately and lack of consensus regarding appropriate quality metrics may lead to variability in performance. Our provision of a structured education programme with feedback will evaluate the impact of individualised training and identify the factors related to improved radiologist performance in CTC reporting. An improvement in performance could lead to increased neoplasia detection and better patient outcome. / Registration: Clinical Trials (ClinicalTrials.gov Identifier: NCT02892721); available from: https://clinicaltrials.gov/ct2/show/NCT02892721. NIHR Clinical Research Network (CPMS ID 32293)