Assessing the construct validity of the Quality-of-Life-Aged Care Consumers (QOL-ACC): an aged care-specific quality-of-life measure.

PURPOSE: To evaluate the construct (convergent and known group) validity of the Quality-of-Life-Aged Care Consumer (QOL-ACC), an older-person-specific quality-of-life measure designed for application in quality assessment and economic evaluation in aged care. METHODS: Convergent validity was assessed by examining relationships with other validated preference-based measures (EQ-5D-5L, ASCOT), quality of aged care experience (QCE-ACC) and life satisfaction (PWI) through an online survey. Known-group validity was assessed by testing the ability to discriminate varying levels of care needs, self-reported health and quality of life. RESULTS: Older people (aged ≥ 65 years) receiving community-aged care (N = 313) responded; 54.6% were female, 41.8% were living alone and 56.8% were receiving higher-level care. The QOL-ACC and its six dimensions were low to moderately and significantly correlated with the EQ-5D-5L (correlation co-efficient range, ρ = 0.39-0.56). The QOL-ACC demonstrated moderate and statistically significant correlations with ASCOT (ρ = 0.61), the QCE-ACC (ρ = 0.51) and the PWI (ρ = 0.70). Respondents with poorer self-reported health status, quality of life and/or higher-level care needs demonstrated lower QOL-ACC scores (P < 0.001), providing evidence of known-group validity. CONCLUSIONS: The study provides evidence of the construct validity of the QOL-ACC descriptive system. A preference-weighted value set is currently being developed for the QOL-ACC, which when finalised will be subjected to further validation assessments.

Weighting and valuing quality-adjusted life-years using stated preference methods: preliminary results from the Social Value of a QALY Project.

OBJECTIVES: To identify characteristics of beneficiaries of health care over which relative weights should be derived and to estimate relative weights to be attached to health gains according to characteristics of recipients of these gains (relativities study); and to assess the feasibility of estimating a willingness-to-pay (WTP)-based value of a quality-adjusted life-year (QALY) (valuation study). DESIGN: Two interview-based surveys were administered - one (for the relativities study) to a nationally representative sample of the population in England and the other (for the valuation study) to a smaller convenience sample. SETTING: The two surveys were administered by the National Centre for Social Research (NatCen) in respondents' homes. PARTICIPANTS: 587 members of the public were interviewed for the relativities study and 409 for the valuation study. METHODS: In the relativities study, in-depth qualitative work and considerations of policy relevance resulted in the identification of age and severity of illness as relevant characteristics. Scenarios reflecting these, along with additional components reflecting gains in QALYs, were presented to respondents in a series of pairwise choices using two types of question: discrete choice and matching. These questions were part of a longer questionnaire (including attitudinal and sociodemographic questions), which was administered face to face using a computer-assisted personal interview. In the valuation study, respondents were asked about their WTP to avoid/prevent different durations of headache or stomach illness and to value these states on a scale (death = 0; full health = 1) using standard gamble (SG) questions. RESULTS: Discrete choice results showed that age and severity variables did not have a strong impact on respondents' choices over and above the health (QALY) gains presented. In contrast, matching showed age and severity impacts to be strong: depending on method of aggregation, gains to some groups were weighted three to four times more highly than gains to others. Results from the WTP and SG questions were combined in different ways to arrive at values of a QALY. These vary from values which are in the vicinity of the current National Institute for Health and Clinical Excellence (NICE) threshold to extremely high values. CONCLUSIONS: With respect to relative weights, more research is required to explore methodological differences with respect to age and severity weighting. On valuation, there are particular issues concerning the extent to which 'noise' and 'error' in people's responses might generate extreme and unreliable figures. Methods of aggregation and measures of central tendency were issues in both weighting and valuation procedures and require further exploration.

Antenatal care for first time mothers: a discrete choice experiment of women's views on alternative packages of care.

OBJECTIVE: To investigate the views of women in relation to the provision of antenatal care. METHODS: A discrete choice experiment using a sample of 100 women who were nulliparous (pregnant for the first time) and attending for routine ultrasound scan in the 20th week of their pregnancy. RESULTS: Women preferred antenatal care visits to be provided by a community midwife at a local clinic and to have 10 visits rather than 7. In addition they favoured the provision of education/preparation for birth, the use of uterine artery Doppler screening, and the provision of a telephone advice line. The results show that women were prepared to trade-off fewer antenatal care visits to ensure access to their packages of antenatal care that reflected their preferences. CONCLUSIONS: Whilst the number of antenatal care visits is important to women they may accept fewer visits if antenatal care is provided by midwives and they receive enhanced service provision such as a telephone advice line and uterine artery Doppler screening.