A tactile pain evaluation scale for persons with visual deficiencies

Abstract

Objective Pain evaluation scales often rely on the sense of sight. There is so far no pain assessment scale specifically designed for persons with visual impairment. Design This study aims to validate a tactile pain evaluation scale, Visiodol©, in blind/visually impaired persons, by correlation with a numeric pain scale (NPS). Setting The study took place in University Hospital Clermont-Fd, France Methods Pain intensity for a range of thermal stimuli (Pathway Medoc®) was evaluated with Visiodol© and NPS; secondary outcomes including pain thresholds, catastrophizing, emotion and quality of life were compared in blind/visually impaired and sighted persons. Lin’s concordance correlation coefficient was estimated; weighted Cohen κ accounted for degrees of disagreement between scales with 95% confidence interval (95%CI). Subjects 21 healthy sighted and 21 healthy non-sighted volunteers (n = 13 congenital, n = 8 acquired) were included. Results Lin’s correlation coefficient for repeated data was 0.967 (95%CI, 0.956; 0.978; P < 0.001) for visually impaired participants with a good agreement at each temperature plateau. Weighted Cohen κ of 0.90 (95% CI, 0.84–0.92) and 92.9% percentage of agreement for visually impaired participants was satisfactory. Pain perception, psychological components and quality of life were more impaired in blind/visually impaired persons than in sighted persons. Conclusions This study validates Visiodol©, a tactile scale for blind/visually impaired persons and addresses healthcare inequalities in the context of pain evaluation. It will now be tested on a larger population of patients in order to give the millions of blind/visually impaired persons worldwide, an option for pain intensity evaluation in clinical situations.