Measuring health-related quality of life in facioscapulohumeral muscular dystrophy: a COSMIN systematic review and conceptual framework

Background

Facioscapulohumeral muscular dystrophy (FSHD) is a common hereditary myopathy causing progressive muscle weakness. FSHD has substantial impacts on function and health-related quality of life (HRQoL). Patient-reported outcome measures (PROs) are used to assess HRQoL, yet their suitability for FSHD remains unclear.

Objectives

(1) identify PROs used to assess HRQoL in adults with FSHD; (2) evaluate the evidence for their measurement properties; and (3) develop a conceptual HRQoL framework for FSHD.

Methods

A systematic review was conducted in accordance with COSMIN and PRISMA-COSMIN guidelines (PROSPERO: CRD42024605345). Two-stage searches across seven databases (including MEDLINE, Embase, and CINAHL, last updated July 2025) identified PROs assessing HRQoL in FSHD and studies evaluating their measurement properties. Eligibility criteria included publicly available, multi-item self-report PROs scored using established systems. Screening, data extraction, and quality appraisal were performed in duplicate. Measurement properties were rated using COSMIN standards and graded with the COSMIN-modified GRADE approach. Item content of the PROs was examined, mapped to an existing framework, and subsequently refined with people living with FSHD to develop a novel HRQoL framework for FSHD (QUAL-FSHD).

Results

Fifty-six development papers and 40 research studies were included in the review, 37 studies reported data on psychometric properties. Sixty-six PROs/subscales were included. Most had evidence limited to content validity (i.e., development papers in non-FSHD populations) and construct validity. Only the Upper Extremity Functional Index (UEFI) had data across five measurement properties, though overall evidence quality was very low to moderate. Responsiveness was assessed in nine PROs, with five determined to be ‘sufficient’. The QUAL-FSHD framework comprises seven themes and 44 subthemes. Mapping of the PROs found 21% (n = 14) covered aspects of physical, psychological, and social functioning, with no instrument covering all subthemes.

Conclusions

Current publicly available HRQoL PROs used in FSHD exhibit significant gaps in content coverage and psychometric evidence to support their use in the condition. The QUAL-FSHD framework provides a structured, stakeholder-informed model for evaluating HRQoL in FSHD. There is an urgent need for future research to establish content validity, psychometric performance, and acceptable respondent burden of existing PROs to ensure accurate assessment of HRQoL outcomes in FSHD.Trial registrationNot applicable.