Measuring quality of life in care homes when self-report is challenging: the construct validity, structural characteristics and internal consistency of the mixed-methods adult social care outcomes toolkit

Abstract

Introduction The adult social care outcomes toolkit (ASCOT) measures social care-related quality of life (SCRQoL) using self-completion questionnaires and interviews. Many care home residents find such methods inaccessible, leading to a reliance on proxy-reporting. This study aimed to establish the psychometric properties of the mixed-methods toolkit [ASCOT-Care Homes, 4 outcome (CH4)] for measuring SCRQoL when residents cannot self-report. Methods Two cross-sectional, mixed-methods studies were undertaken in care homes for older people in England between 2015 and 2020. We used the ASCOT-CH4 (observation, and interviews with residents and proxies) to collect information about SCRQoL and collected additional data on residents’ needs and characteristics, and variables hypothesised to be related to SCRQoL. Hypothesis testing was applied to establish construct validity, Cronbach’s alpha for internal consistency and exploratory factor analysis for structural validity. Results The combined dataset included 475 residents from 54 care homes (34 nursing, 20 residential). Half had a diagnosis of dementia. Less than a third of residents were able to complete an ASCOT interview. Observations and proxy interviews informed researcher ratings, meaning there were no missing ASCOT-CH4 scores. ASCOT-CH4 was found to be a weak unidimensional scale, consistent with other ASCOT measures, with acceptable internal consistency (α = 0.77, 8 items). Construct validity was supported by the findings. Conclusions The ASCOT-CH4 is an alternative to conventional proxy-questionnaires for measuring the SCRQoL of care home residents, with good psychometric properties. A limitation is that users need a range of data collection skills. Future research should explore whether findings are replicable when data are collected by other researchers.

Factors associated with care home resident quality of life: Demonstrating the value of a pilot Minimum Data Set using cross-sectional analysis from the DACHA study

“…In so doing, the study has demonstrated both the value of the DACHA study pilot MDS data, especially in collecting resident QoL, and a rationale for the inclusion of these three QoL measures in any future MDS. [7,[14][15]25]. Y…”

“…These include the Adult Social Care Outcomes Toolkit (ASCOT) and the ICEpop CAPability measure for older people (ICECAP-O). ASCOT is a suite of social care related QoL measures and is suitable for use in care homes [5][6][7]). ICECAP-O is a measure of QoL from a capability wellbeing perspective, assessing whether a person can do the things that are important to them in life [8][9].…”

Cross-sectional study assessing the feasibility of measuring residents’ Quality of Life in English care homes and assessing the construct validity and internal consistency of measures completed by staff-proxy

“…COSMIN reporting guidance advises that an assessment of internal consistency is not required for formative measures [64]. Preference-based measures (EQ-5D-5L, ASCOT and ICECAP) are generally accepted to be formative [75], however for comparability with previous research [26,29,35], we have assessed internal consistency in this study. We used the COSMIN Study Design Checklist rule of thumb for adequacy of sample size for EFA, internal consistency and construct validity by hypothesis testing.…”

“…However, an adapted version for proxy-report by staff (without the use of dual proxy perspectives) is included in the care homes version (CH4) of ASCOT. This is a feasible, valid and reliable measure, with a higher % completion and better coverage than family carer proxy report [29,30]. Two recent studies of the ASCOT-Proxy completed by family carers of people with dementia, living at home, and also with care home residents using the DACHA study sample, have found that of the two measures, only the ASCOT-Proxy-Person/Resident has the same structural characteristics as the original ASCOT self- completion version (SCT4) from which the ASCOT-Proxy was adapted [49,50].…”

“…The mode of completion (self-complete/proxy) is critical: response rates to QoL measures amongst care home residents are very low, with relatively few residents able to self-report [4,[29][30][31] highlighting a significant methodological challenge regarding the routine measurement of QoL in care/nursing homes for older adults. Staff acting as proxies for residents can be controversial when measuring QoL, mostly due to concerns of bias [32,33], despite staff frequently collecting data about residents' physical, psychological and social status to inform assessments and care planning [34].…”