Quality of instruments assessing activity and participation of people with muscular dystrophy: A systematic review of participant-reported outcome measures

Aim: To identify the standardized assessment scales for people with muscular dystrophy and investigate the quality/level of evidence of their measurement properties.

Method: A systematic review of patient-reported outcome measures was conducted on the MEDLINE, Embase, AMED, DiTA, and PsycINFO databases in August 2020. We included psychometric studies that investigated the validity, reliability, and responsiveness of instruments assessing activity and participation for muscular dystrophy of any type (Duchenne, Becker, limb-girdle, facioscapulohumeral, congenital, and myotonic) or age. Two independent reviewers selected the studies, extracted data, and evaluated the instruments' quality and level of evidence following the COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN) checklist. The study followed the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) 2020 guidelines.

Results: The searches identified 6675 references; a total of 46 studies with 28 condition-specific or general instruments were included. The measurement properties of most instruments had sufficient (68.8%) or indeterminate (25.7%) results according to COSMIN. The quality of evidence of the measurement properties was moderate (23.8%) or low (22.6%) according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE).

Interpretation: There is a lack of high-quality instruments whose psychometric properties are adequately measured. The highest quality instrument is the Muscular Dystrophy Functional Rating Scale. The Motor Function Measure (general instrument), Duchenne Muscular Dystrophy Upper-limb Patient-reported Outcome Measure, North Star Ambulatory Assessment, and Myotonic Dystrophy Type 1 Activity and Participation Scale for Clinical Use (specific) are also recommended.

What this paper adds: There are 28 available instruments for activity and participation of people with muscular dystrophy. The evidence quality is moderate or low because of imprecision and indirectness. The Muscular Dystrophy Functional Rating Scale is the highest quality instrument. The Motor Function Measure is the second most recommended instrument. The Duchenne Muscular Dystrophy Upper-limb Patient-reported Outcome Measure, North Star Ambulatory Assessment, and Myotonic Dystrophy Type 1 Activity and Participation Scale for Clinical Use are also recommended.