extended · article · 2026

Large‐Scale Psychometric Assessment and Validation of the Modified COVID‐19 Yorkshire Rehabilitation Scale Patient‐Reported Outcome Measure for Long COVID or Post‐COVID Syndrome

Mike Horton; Adam B. Smith; Ruairidh Milne; Darren Winch; Clare Rayner; Stephen Halpin; Rory S. O’Connor; Román Rocha Lawrence; Darren C. Greenwood; Nawar D. Bakerly; Rachael A Evans; Joseph Kwon; Helen Dawes; Conor Wood; Paul Williams; Harsha Master; Mae Mansoubi; Johannes H. De Kock; Jordan Mullard; M Ormerod; Ghazala Mir; Stavros Petrou; Daryl B. O'Connor; Manoj Sivan; Everett V. Smith Jr.

The C19-YRS was the first condition-specific for long COVID/post-COVID syndrome. Although the original C19-YRS evolved to the modified version (C19-YRSm) based on psychometric evidence, clinical content relevance, as well as feedback from patients and healthcare professionals, it has not been validated through Rasch analysis. The study aim was to psychometrically assess and validate the C19-YRSm using newly collected data from a large-scale, multicenter study (LOCOMOTION). In total, 1278 patients (67% Female; mean age = 48.6, SD 12.7) digitally completed the C19-YRSm. The psychometric properties of the C19-YRSm Symptom Severity (SS) and Functional Disability (FD) subscales were assessed using a Rasch Measurement Theory framework, assessing for individual item model fit, targeting, internal consistency reliability, unidimensionality, local dependency (LD), response category functioning an...