Qualitative testing of potential modifications to the EQ-HWB-9 v1.2 in adults with mobility problems in the United Kingdom

Background

The EQ-Health and Wellbeing (EQ-HWB) is a generic measure assessing the impact of health, social care, and informal caregiving on quality of life. The 9-item short form, the EQ-HWB-9 v1.1 (experimental, 2022), underwent international validation, with subsequent modifications to item wording, response options, layout, and item order resulting in the EQ-HWB-9 v1.2 (experimental modified, 2024). This study aimed to assess the content validity of this version in individuals with mobility problems.

Methods

Twelve adults in the UK with self-reported health conditions and mobility problems participated in semi-structured interviews. Participants described their health experiences, reviewed each EQ-HWB-9 v1.2 item, and compared potential further modifications to the ‘mobility’ item wording and ‘cognition’ response options. Comprehension, relevance, comprehensiveness and preferences were explored using verbal probing. Interviews were transcribed and analysed using framework analysis, guided by content validity domains, with double-coding for 25% of transcripts to ensure alignment.

Results

Participants (age 35–79 years) reported 35 health conditions. Eight items were understood as intended by all participants. The ‘mobility’ item presented varied interpretations (home-based limitations, daily activities, or aid use, n = 4), highlighting the need for an illustrative example, though no single wording was universally preferred. For ‘cognition’, participants understood both frequency and difficulty response scales; preferences were split, indicating no required modifications. Some overlap between items was noted (‘mobility’-‘activities’, ‘cognition’-‘exhaustion’/’anxiety’/’pain’), but participants did not perceive redundancy and valued separate items for nuanced measurement. Most items were considered relevant, and participants suggested additional content on medical management, support, mental health impact, and free-text contextualisation. The seven-day recall period and instructions were generally well understood.

Conclusion

The EQ-HWB-9 v1.2 demonstrates good content validity in a sample of patients with mobility problems, with most items comprehensible and relevant. The ‘mobility’ item would benefit from an example to reduce interpretive variability, while ‘cognition’ response options are appropriate. Some item overlap is expected in complex health populations, yet distinctions between items are meaningful. Participants highlighted the importance of healthcare experiences in quality-of-life assessment. These results inform instrument refinement, but final changes should integrate broader evidence from global validation studies across other populations and languages.