Evaluating the Validity of the EQ-HWB-9 in a Large United Kingdom General Population Sample

The EQ Health and Well-being (EQ-HWB-9) is a preference-weighted instrument with an interim value set for assessing health and well-being in patients, social care users, and carers. This study evaluated the experimental (2022) version's psychometric properties and compared it with established measures in a UK general population sample.

Data were drawn from a large cross-sectional survey of the UK general population (n = 11 383). Ceiling/floor effects were assessed at item (>50% extreme responses) and instrument (>15% at min/max score) levels. Convergent validity was assessed using Spearman correlations between EQ-HWB-9 items and conceptually similar items from the Short Warwick-Edinburgh Mental Well-being Scale, ICEpop CAPability measure for Adults, Health Utilities Index Mark 3 (HUI3), Office for National Statistics 4 Personal Well-being Questions, and Systems-science In Public Health and Health Economics Research. Pearson correlations were used for utility scores. Known-group validity was assessed using effect sizes (ES) to examine differences by mental well-being, disability, life satisfaction, caregiving status, self-reported health, and age. Agreement with comparator instruments was assessed using Bland-Altman plots and Lin's concordance correlation coefficient.

Potential ceiling effects were noted for EQ-HWB-9 mobility and activity items, but not at the instrument level. Strong correlations (rs≥0.5, p<.001) with measures hypothesized a priori to assess related constructs (Short Warwick-Edinburgh Mental Well-being Scale, ICEpop CAPability measure for Adults, HUI3, Office for National Statistics 4 Personal Well-being Questions, and Systems-science In Public Health and Health Economics Research) supported convergent validity. The EQ-HWB-9 effectively distinguished between relevant population subgroups (ES ≥0.8). Agreement with HUI3 utilities was higher (concordance correlation coefficients >0.75) than with other comparators.

The EQ-HWB-9 shows strong psychometric performance and is supported for use in UK health and well-being assessments.