A single patient reported outcome measure for acquired brain injury, multiple sclerosis & Parkinson's disease

Abstract

Objective: To determine psychometric properties of the PROMIS-10 and Standard Stroke Question Set (by International Consortium for Health Outcome Measures) presented as a new 15- item Patient Related Outcome (PRO), for patients with: acquired Brain Injury (ABI), Multiple sclerosis (MS) and Parkinson's disease (PD). Methods: In an eight centre, UK wide, cross-sectional study we approached patients during their routine follow-up to complete: a disease-specific instrument (European Brain Injury Questionnaire, Multiple Sclerosis Impact Scale, and Parkinson's disease questionnaire); General Health questionnaire with a Quality of life measure (EQ-5D); and PRO. We validated the PRO using factor analysis to define the latent construct domains, then calculated the internal consistency (Cronbach's-α), and construct validity (correlation). Results: There were 340 patients with ABI (N = 91, median age = 55.1, 41% female), MS (N = 99, age = 58.9, 69%) and PD (N = 150, age = 74.5, 40%). Factor analysis suggested the PRO offered three domains of: physical health; functionality-capacity and mental health. All factors correlated strongly with the three disease-specific instruments, and the overall PRO had a large correlation with the EQ-5D (correlation>0.8) offering good construct validity and excellent internal consistency (α>0.89). Interpretation The PRO offered promising psychometric properties and could be used in place of disease specific questionnaires for patients with ABI, MS, and PD. The PRO has three construct domains, describing patients': mental health; physical health; and functional-capacity, and may be used in routine clinical practice. The PRO offered both relevance to each of the three separate neurological conditions and generalisability across all the conditions, increasing its utility.