An assessment of the construct validity of the icecap-o index of capability in Australian national transition care and clinical rehabilitation programmes : Paper presented to the MRC HTMR Workshop on The use of ICECAP measures in clinical trials and economic evaluation
(C) Copyright Flinders University 2011.
Aims: The ICECAP-O index of capability is a new instrument designed to measure and value the quality of life of older people. Advantages of the ICECAP-O include its focus upon a broader concept of quality of life than health alone and its potential for application in economic evaluation across health, transition care and aged care sectors. This study aimed to determine the construct validity of the ICECAP-O in care transition and clinical rehabilitation programmes for older people. Methods: A questionnaire containing the ICECAP-O was administered using a face to face interview mode of administration with patients participating in in-patient medical rehabilitation (n=100), out-patient day rehabilitation (n=55) and the Australian National Transition Care Programme (n=26). The relationships between the ICECAP and other instruments including the EQ-5D, Herth Hope Index, Modified Rankin Scale (a measure of disability completed by the health care professional), CTM-3 (quality of care transitions) and socio-demographic characteristics were examined. Results: The mean ICECAP-O scores for all three groups were broadly similar (in-patient; mean 0.759, range 0.390-1.000; out-patient mean 0.815, range 0,410-1.000; transition care mean 0.788, range 0.436-1.000). The ICECAP-O was found to be inversely correlated with the Modified Rankin Scale (Spearman’s r = -0.286; P < 0.01) indicating that as the level of disability increased, capability decreased. The ICECAP was also found to be positively correlated with the EQ5D (Spearman’s r = 0.418; P<0.01) and the Herth Hope index (Spearman’s r =0.402; P<0.01) and positively correlated with the quality of care transitions as measured by the CTM-3 instrument (Spearman’s r = 0.259; P=0.0291). The distribution of responses to the ICECAP-O indicated that whilst the majority of participants reported high levels of love and friendship, many participants expressed some concern about their future and reported limitations in their independence and ability to do things that made them feel valued. In general, participants reported more problems in relation to the physical dimensions of the EQ-5D (mobility, self care and usual activities) and EQ-5D values were on average well below general population norm levels for this age group (mean 0.53, SD 0.32). Conclusion: The findings from this study demonstrate the strong empirical relationships between the concepts of health, disability, hope and capability and provide support for the construct validity of the ICECAP-O in clinical rehabilitation and transition care settings. Relationships between the ICECAP-O and other measures were mostly as anticipated indicating that whilst health related Page 3 of 26quality of life and hope were positively associated with capability, the level of disability and older person’s perceptions of poor quality care transitions impacted negatively upon capability. The ICECAP-O shows promise in providing a new and rigorous approach to the measurement and valuation of quality of life for future application in economic evaluation across health, transition care and aged care sectors.
Copyright Flinders University 2011. Paper presented to the MRC HTMR Workshop on The use of ICECAP measures in clinical trials and economic evaluation, University of Birmingham, February 15th-16th 2011.
ICECAP-O, quality of life of older people, transition care, aged care, rehabilitation
• Ratcliffe J, Laver K, Couzner L, Crotty M. An assessment of the construct validity of the ICECAP-O index of capability in Australian national transition care and clinical rehabilitation programmes. Flinders University Working Paper (2011)