Do Generic Preference-Based Measures Accurately Capture Areas of Health-Related Quality of Life Important to Individuals with Amyotrophic Lateral Sclerosis: A Content Validation Study

• Published in: Patient related outcome measures Vol. 12; pp. 191 - 203
• Main Authors: Peters, Nicole, Dal Bello-Haas, Vanina, Packham, Tara, Chum, Marvin, O'Connell, Colleen, Johnston, Wendy S, MacDermid, Joy C, Turnbull, John, Van Damme, Jill, Kuspinar, Ayse
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 01.01.2021; Taylor & Francis Ltd; Dove; Dove Medical Press
• Subjects: Amyotrophic lateral sclerosis; Cost analysis; economic evaluation; health-related quality of life; Interpersonal relations; Original Research; patient reported outcome measures; Printed materials; psychometric properties; Quality of care; Quality of life; Questionnaires; Sociodemographics; Validity; Canada; patient reported outcome measures; health-related quality of life; psychometric properties; economic evaluation; amyotrophic lateral sclerosis
• ISSN: 1179-271X; 1179-271X
• DOI: 10.2147/PROM.S313512

The objectives of this study were to 1) assess the content validity of generic preference-based measures (GPBMs), and (2) examine the convergent validity of the EuroQol 5 Dimension 5 Level (EQ-5D-5L), against the Patient Generated Index (PGI) in Amyotrophic Lateral Sclerosis (ALS). Participants were recruited from 3 clinical sites across Canada. The PGI, EQ-5D-5L and Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) were administered through an online or hardcopy survey and scores compared for convergent validation. Domains nominated by participants as important to their health-related quality of life were generated using the PGI, classified using the International Classification of Functioning, Disability and Health (ICF) and mapped onto GPBMs to determine content coverage. Fifty-two participants (N=28 female; 61.3 ± 11.6 mean age ± standard deviation (SD); 3.5 ± 2.9 mean ± SD years since diagnosis) completed this study. The top three ICF domains identified by participants were recreation and leisure, lower limb mobility, and interpersonal relationships. The Quality of Well-Being Self-Administered (QWB-SA) scale had the highest content coverage (87%) and the Health Utilities Index 3 (HUI3) had the lowest (33%). Two domains were covered by all GPBMs and no GPBM included all domains identified as important by participants. A moderate correlation coefficient of 0.52 between the PGI and EQ-5D-5L was found. The majority of GPBMs covered only approximately half of the domains important to individuals with ALS suggesting the need for an ALS specific preference-based measure to better reflect the health-related quality of life of this population.