Quality of life measurement in people with multiple long-term conditions: a co-produced scoping review and visual evidence map

Adults with multiple long-term conditions (MLTC) have complex health challenges that can affect their quality of life (QoL), yet existing QoL measures remain largely generic and might not capture the complexity of MLTC. In this scoping review, we systematically mapped the development and use of QoL measures in adults with MLTC. QoL tools were identified, and measure components were charted using WHO’s International Classification of Functioning, Disability and Health (ICF). Patient and public representatives contributed to the methodology, interpretation, and co-production of a visual evidence map to support knowledge translation, including identifying whether current measures capture what matters most to people with MLTC. 77 studies encompassing 754 029 participants were included, mostly conducted in primary care settings (42 [55%]) and defining MLTC as the co-existence of two or more conditions (53 [69%]). Overall, 18 measures derived from eight core QoL scales were identified, with the EuroQol family most frequently used (50 [65%] of 77 studies). Only two measures were developed specifically for populations with MLTC, although neither has subsequently been used to assess QoL in people with MLTC. One measure was validated in populations with MLTC but rarely used (2 [3%] of 77 studies). ICF mapping revealed that components predominantly captured activities and participation (236 [41%] of 574 components) and body functions (188 [33%]), with low coverage of environment (75 [13%]). Our findings highlight that generic QoL measures dominate despite their low capacity to fully capture the complexity of MLTC. QoL measurement requires person-centred and flexible approaches that better reflect the diverse experiences of people with MLTC.