TY - JOUR T1 - Comparing the Visual Analog Scale and the Numerical Rating Scale in Patient-reported Outcomes in Psoriatic Arthritis JF - The Journal of Rheumatology JO - J Rheumatol DO - 10.3899/jrheum.200928 SP - jrheum.200928 AU - Weiyu Ye AU - Simon Hackett AU - Claire Vandevelde AU - Sarah Twigg AU - Philip S. Helliwell AU - Laura C. Coates Y1 - 2020/12/01 UR - http://www.jrheum.org/content/early/2021/04/10/jrheum.200928.abstract N2 - Objective Patient self-report scales are invaluable in psoriatic arthritis (PsA), as they allow physicians to rapidly assess patient perspectives of disease activity. We aimed to assess the agreement of the visual analog scale (VAS), a 100-mm horizontal line, and the numerical rating scale (NRS), a 21-point scale ranging from 0 to 10 in increments of 0.5, in patients with PsA. Methods Data were collected prospectively across 3 UK hospital trusts from 2018 to 2019. All patients completed the VAS and NRS for pain, arthritis, skin psoriasis (PsO), and global disease activity. A subset completed an identical pack 1 week later. Demographic and clinical data were also collected. Agreement was assessed using medians and the Bland-Altman method. Intraclass correlation coefficients (ICCs) were used to assess test-retest reliability. Spearman rank correlation coefficients were used to assess dependency between scale scores and clinical variables. Results Two hundred ten patients completed the study; 1 withdrew consent. Thus, 209 were analyzed. For pain, arthritis, skin PsO, and global disease activity, the difference between the VAS and NRS lay mostly within 1.96 SD of the mean, suggesting reasonable agreement between the 2 scales. Among the patients, 64.1% preferred the NRS. The ICCs demonstrated excellent test-retest reliability for both VAS and NRS. Higher VAS and NRS scores were associated with increased tender/swollen joint count, poorer functional status, and greater life impact. Conclusion The VAS and NRS show reasonable agreement in key patient-reported outcomes in PsA. Results from both scales are correlated with disease severity and life impact. ER -