Validation of the MASK-rhinitis visual analogue scale on smartphone screens to assess allergic rhinitis control

Background Visual Analogue Scale (VAS) is a validated tool to assess control in allergic rhinitis patients. Objective The aim of the present study was to validate the use of VAS in the MASK-rhinitis (MACVIA-ARIA Sentinel NetworK for allergic rhinitis) App (Allergy Diary) on smartphones screens to evaluate allergic rhinitis symptoms and disease control. Methods Each user filled 4 different VAS measuring overall, nasal, ocular and asthma symptoms at least once. Following COSMIN guidelines, we evaluated internal consistency, (Cronbach's alpha-coefficient and test-retest), reliability (intraclass correlation coefficients), sensitivity and acceptability, of the MASK-Rhinitis VAS. Results Between August 1st, 2015 and July 31st, 2016, the app was used 14,612 times in 15 countries. 1,225 users used it more than once, during the evaluated period. The tool resulted to be statistically satisfactory, showing excellent internal consistency (Cronbach's test >0.84, test-retest >0.7), reliability (>0.9) and acceptability. In addition, the tool had a good sensitivity when users (n=521) answered the VAS twice in less than three hours. Conclusions & Clinical Relevance The MASK-rhinitis VAS is a reliable and valid tool to assess allergic control on smartphone screens, at the population level. This article is protected by copyright. All rights reserved.