DOES A SLEEP BOLT-ON IMPROVE THE MEASUREMENT OF HEALTH-RELATED QUALITY OF LIFE AMONG COMMUNITY MENTAL HEALTH SERVICE USERS? EVIDENCE FROM HONG KONG
Author(s)
Cindy Y. Tian, PhD, Annie Wai-ling Cheung, MPhil, Jonathan Chun-hei Ma, MPH, Eliza LY Wong, PhD.
JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China.
JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China.
OBJECTIVES: Sleep disturbance is prevalent among people with mental health conditions and is increasingly recognised as an important determinant of health-related quality of life (HRQoL). This study examined the incremental explanatory value of a sleep bolt-on in community mental health service users.
METHODS: We analysed Phase II survey data from 208 community mental health service users in Hong Kong. The EQ-5D-5L and a five-level sleep bolt-on were administered alongside the EQ Visual Analogue Scale (VAS). Ceiling effects were compared with and without the sleep item. Hierarchical regression examined the incremental validity of the sleep bolt-on over the full EQ-5D-5L model and over the anxiety/depression (AD) dimension specifically, adjusting for sociodemographic and clinical covariates. Construct validity was evaluated using known-groups analyses. A Partial Credit Model (PCM) was fitted to evaluate item fit and the measurement performance of the sleep bolt-on alongside the EQ-5D-5L dimensions.
RESULTS: Most participants were females (81%), and 67.8% were aged 50 years or above. Adding the sleep bolt-on reduced the ceiling effect from 20.2% to 8.2%. The sleep item demonstrated significant incremental validity beyond the full EQ-5D-5L model (ΔR²=2.0%, p=0.015) and beyond the AD dimension alone (ΔR²=3.0%, p=0.004). Convergent validity was supported by correlations with AD (ρ=0.35, p<0.001) and pain/discomfort (ρ=0.27, p<0.001). Known-groups validity was demonstrated by greater sleep problem severity among participants with multiple diagnoses than those with a single diagnosis (3.04 vs 2.42, p=0.003). PCM analysis indicated acceptable item fit (Infit MSQ range: 0.741-0.956).
CONCLUSIONS: The sleep bolt-on captured aspects of HRQoL not fully represented by the EQ-5D-5L, reducing ceiling effects and providing additional explanatory value among community mental health service users. Further validation, including valuation studies and longitudinal responsiveness testing, is warranted prior to routine application.
METHODS: We analysed Phase II survey data from 208 community mental health service users in Hong Kong. The EQ-5D-5L and a five-level sleep bolt-on were administered alongside the EQ Visual Analogue Scale (VAS). Ceiling effects were compared with and without the sleep item. Hierarchical regression examined the incremental validity of the sleep bolt-on over the full EQ-5D-5L model and over the anxiety/depression (AD) dimension specifically, adjusting for sociodemographic and clinical covariates. Construct validity was evaluated using known-groups analyses. A Partial Credit Model (PCM) was fitted to evaluate item fit and the measurement performance of the sleep bolt-on alongside the EQ-5D-5L dimensions.
RESULTS: Most participants were females (81%), and 67.8% were aged 50 years or above. Adding the sleep bolt-on reduced the ceiling effect from 20.2% to 8.2%. The sleep item demonstrated significant incremental validity beyond the full EQ-5D-5L model (ΔR²=2.0%, p=0.015) and beyond the AD dimension alone (ΔR²=3.0%, p=0.004). Convergent validity was supported by correlations with AD (ρ=0.35, p<0.001) and pain/discomfort (ρ=0.27, p<0.001). Known-groups validity was demonstrated by greater sleep problem severity among participants with multiple diagnoses than those with a single diagnosis (3.04 vs 2.42, p=0.003). PCM analysis indicated acceptable item fit (Infit MSQ range: 0.741-0.956).
CONCLUSIONS: The sleep bolt-on captured aspects of HRQoL not fully represented by the EQ-5D-5L, reducing ceiling effects and providing additional explanatory value among community mental health service users. Further validation, including valuation studies and longitudinal responsiveness testing, is warranted prior to routine application.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
PCR11
Topic
Methodological & Statistical Research, Patient-Centered Research
Topic Subcategory
Health State Utilities, Patient-reported Outcomes & Quality of Life Outcomes
Disease
Mental Health (including addiction)