Author Of 1 Presentation
P1031 - Exploring the relevance and validity of wellbeing measures that can be used in cost-effectiveness analysis in the context of multiple sclerosis (ID 1878)
Abstract
Background
In recent years, instruments have been developed that provide wellbeing equivalents to the health-related quality-adjusted life-year (QALY) for use in cost-effectiveness analyses (CEA). Little is known about the relevance of these instruments to people with multiple sclerosis (MS) or the implications of their use for decision-making regarding treatments for MS. This research is part of a study that aims to assess two wellbeing measures which can be used in CEA - the Adult Social Care Outcomes Toolkit (ASCOT) and ICEpop CAPability measure for Adults (ICECAP-A) – in the context of MS.
Objectives
To compare the psychometric properties of the ASCOT and ICECAP-A when used with people with MS, with those of two health-related QALY measures designed for use in CEAs: the EuroQol EQ-5D-3L and the Multiple Sclerosis Impact Scale – Eight Dimensions (MSIS-8D).
Methods
Via a literature review and the involvement of with people with MS, we identified significant illness-related events (IREs) that affect the wellbeing of people with MS. We developed a questionnaire for respondents to report whether they had experienced each of 27 IREs over the previous six months. This questionnaire was administered online alongside the ASCOT and ICECAP-A via the UK MS Register. This is a website via which people with MS living in the UK directly complete questionnaires about their MS. Responses were linked to MS Register data: age, gender, type of MS, and responses to the EQ-5D, Multiple Sclerosis Impact Scale (MSIS-29) (from which the MSIS-8D can be calculated), Fatigue Severity Scale (FSS), Hospital Anxiety and Depression Scale (HADS) and Multiple Sclerosis Walking Scale-12 (MSWS-12). The relevance and validity of the wellbeing measures for people with MS were analysed and compared with the EQ-5D and MSIS-8D.
Results
Responses were provided by 2825 people with MS. Completion rates were high for all instruments (³95%). Each of the wellbeing and QALY measures discriminated between groups based on: MS type; published cut-off points for the FSS, HADS and MSWS-12; and incidence of 15 of the IREs including relapses, and changes in treatment, support or employment (p<0.0001). Typically, absolute effect sizes were higher for the EQ-5D, while standardised effect sizes were higher for the MSIS-8D and wellbeing measures.
Conclusions
These psychometric properties of the ASCOT and ICECAP-A wellbeing measures support their use with people with MS. However, their lower absolute effect sizes could result in less favourable outcomes when assessing treatments for MS, compared to the EQ-5D-3L.