Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

BACKGROUND: Crohn's disease (CD) is a lifelong, relapsing and remitting inflammatory condition of the intestine. Medical imaging is crucial for diagnosis, phenotyping, activity assessment and detecting complications. Diverse small bowel imaging tests are available but a standard algorithm for deployment is lacking. Many hospitals employ tests that impart ionising radiation, of particular concern to this young patient population. Magnetic resonance enterography (MRE) and small bowel ultrasound (USS) are attractive options, as they do not use ionising radiation. However, their comparative diagnostic accuracy has not been compared in large head to head trials. METRIC aims to compare the diagnostic efficacy, therapeutic impact and cost effectiveness of MRE and USS in newly diagnosed and relapsing CD. METHODS: METRIC (ISRCTN03982913) is a multicentre, non-randomised, single-arm, prospective comparison study. Two patient cohorts will be recruited; those newly diagnosed with CD, and those with suspected relapse. Both will undergo MRE and USS in addition to other imaging tests performed as part of clinical care. Strict blinding protocols will be enforced for those interpreting MRE and USS. The Harvey Bradshaw index, C-reactive protein and faecal calprotectin will be collected at recruitment and 3 months, and patient experience will be assessed via questionnaires. A multidisciplinary consensus panel will assess all available clinical and imaging data up to 6 months after recruitment of each patient and will define the standard of reference for the presence, localisation and activity of disease against which the diagnostic accuracy of MRE and USS will be judged. Diagnostic impact of MRE and USS will be evaluated and cost effectiveness will be assessed. The primary outcome measure is the difference in per patient sensitivity between MRE and USS for the correct identification and localisation of small bowel CD. DISCUSSION: The trial is open at 5 centres with 46 patients recruited. We highlight the importance of stringent blinding protocols in order to delineate the true diagnostic accuracy of both imaging tests and discuss the difficulties of diagnostic accuracy studies in the absence of a single standard of reference, describing our approach utilising a consensus panel whilst minimising incorporation bias. TRIAL REGISTRATION: METRIC - ISRCTN03982913 - 05.11.13.

Original publication

DOI

10.1186/1471-230X-14-142

Type

Journal article

Journal

BMC Gastroenterol

Publication Date

11/08/2014

Volume

14

Keywords

Adolescent, Adult, Aged, Cohort Studies, Cost-Benefit Analysis, Crohn Disease, Humans, Intestine, Small, Magnetic Resonance Imaging, Middle Aged, Prospective Studies, Recurrence, Ultrasonography, Young Adult