Preference-based Quality Of Life Measure Research Articles

Valuing the Dental Caries Utility Index in Australia.

The Dental Caries Utility Index (DCUI) is a new oral health-specific health state classification system for adolescents, consisting of 5 domains: pain/discomfort, difficulty eating food/drinking, worried, ability to participate in activities, and appearance. Each domain has 4 response levels. This study aims to generate an Australian-specific utility algorithm for the DCUI. An online survey was conducted using a representative sample of the adult Australian general population. The discrete choice experiment (DCE) was used to elicit the preferences on 5 domains. Then, the latent utilities were anchored onto the full health-dead scale using the visual analogue scale (VAS). DCE data were modeled using conditional logit, and 2 anchoring procedures were considered: anchor based on the worst health state and a mapping approach. The optimal anchoring procedure was selected based on the model parsimony and the mean absolute error (MAE). A total of 995 adults from the Australian general population completed the survey. The conditional logit estimates on 5 dimensions and levels were monotonic and statistically significant, except for the second level of the "worried" and "appearance" domains. The mapping approach was selected based on a smaller MAE between the 2 anchoring procedures. The Australian-specific tariff of DCUI ranges from 0.1681 to 1. This study developed a utility algorithm for the DCUI. This value set will facilitate utility value calculations from the participants' responses for DCUI in economic evaluations of dental caries interventions targeted for adolescents. Preference-based quality-of-life measures (PBMs), which consist of a health state classification system and a set of utility values (a scoring algorithm), are used to generate utility weights for economic evaluations.This study is the first to develop an Australian utility value set for the Dental Caries Utility Index (DCUI), a new oral health-specific classification system for adolescents.The availability of a utility value set will enable using DCUI in economic evaluations of oral health interventions targeted for adolescents and may ultimately lead to more effective and efficient planning of oral health care services.

The Feasibility and Validity of Preference-Based Quality of Life Measures With Informal Carers: A Think-Aloud Study

ObjectivesA range of preference-based quality of life (QoL) measures have been proposed for use with informal carers. Qualitative evaluation of validity and feasibility of the measures is an important step in understanding whether measures will work as intended. At present, little is known about the performance of different types of preference-based QoL measures with informal carers. The objective of this study was to qualitatively assess the feasibility, content validity (including face validity), and acceptability of 5 QoL measures (the Carer Experience Scale, CarerQoL-7D, ASCOT-C, ICECAP-A, and EQ-5D-5L) with informal carers. MethodsA total of 24 “think-aloud” interviews were conducted with a cross-section of carers of adults in the United Kingdom. This think-aloud process was followed by semistructured discussion to probe issues of validity and feasibility in more detail. The interview data were transcribed, coded to identify the frequency of errors in completing the QoL measures and thematically analyzed to study the validity, feasibility, and acceptability of the measures. ResultsFew errors (3%-7% per item) were identified in completing each of the measures with little distinct pattern. Most participants found the measures to be concise, clear, and relevant. Challenges included relevance, context, time period, missing items, multiple questions, and response options. Informal carers generally expressed a preference for using a care-related QoL measure. ConclusionsExisting preference-based QoL measures have encouraging validity and feasibility within a mixed sample of informal carers, with minor challenges raised. These challenges ought to be considered, alongside the decision context, when administering QoL measures in this context.

Producing a preference-based quality of LIFE measure to quantify the impact of HYPOGLYCAEMIA on people living with diabetes: A mixed-methods research protocol.

Assessment of patient-reported outcome measures (PROMs), including quality of life (QoL), is essential in diabetes research and care. However, a recent review concluded that current hypoglycaemia-specific PROMs have limited evidence of validity, reliability and responsiveness for assessing the impact of hypoglycaemia on QoL in people living with diabetes. None of the PROMs identified could be used directly to inform the cost-effectiveness of treatments and interventions. There is a need for a new hypoglycaemia-specific QoL PROM, which can be used directly to inform economic evaluations. This project has three aims: (a) To develop draft PROM content for measuring the impact of hypoglycaemia on QoL in adults with diabetes. (b) To refine the draft content using cognitive debriefing interviews and psychometrics. This will result in a condition-specific PROM that can be used to quantify the impact of hypoglycaemia upon QoL. (c) To generate a preference-based measure (PBM) that will enable utility values to be calculated for economic evaluation. A mixed-methods, three-stage design is used: (a) Qualitative interviews will inform the draft PROM content. (b) Cognitive debriefing interview data will be used to refine the draft PROM content. The PROM will be administered in a large-scale survey to enable psychometric validation. Final item selection for the PROM will be informed by psychometric performance, translatability assessment and input from stakeholder groups. (c) A classification system will be generated, comprising a reduced number of items from the PROM. A valuation survey will be conducted to derive a value set for the PBM.

Development of a classification (descriptive) system for a preference-based quality of life measure for dental caries (dental caries utility index) among adolescents.

Preference-based quality-of-life measures (PBMs) have been developed in many clinical areas to aid estimation of more accurate utility values for economic evaluations. Existing oral health-related quality-of-life (OHRQoL) instruments are non-PBM and hence, cannot be used to generate utility values. The objective of this study was to develop a classification system for a new PBM (dental caries utility index-DCUI) for the most prevalent childhood oral health condition: dental caries. Possible domains and items to be included in the classification system were identified based on the reviewing available pediatric non-PBM OHRQoL instruments, studies eliciting utility values for oral health outcomes and clinical dentistry textbooks and based on the findings, a draft classification system was developed. To refine the draft classification system, semi-structured interviews were conducted among a convenience sample of 15 12-17-year-old adolescents who had experience with dental caries. The classification system was further refined and validated by a group of dental experts, using a modified Delphi technique. The classification system comprised five items (pain/discomfort, difficulty in eating food/drinking, worried, ability to participate in activities, and appearance) and each item had a four-level response scale. The classification system developed herein is considered an amenable tool for the subsequent development of a new PBM for dental caries. Once the scoring algorithm is completed, the classification system can be used to incorporate economic evaluations of dental caries health interventions.

Assessing the relative importance of key quality of life dimensions for people with and without a disability: an empirical ranking comparison study

BackgroundIn economic evaluation, the quality of life of people with a disability has traditionally been assessed using preference-based instruments designed to measure and value quality of life. To provide robust measurement of the effectiveness of programs designed to improve the quality of life of people living with a disability, preference-based measures need to be sufficiently sensitive to detect incremental changes in the quality of life dimensions that are most important to people who have a disability. This study sought to explore whether there was a difference in the ranked order of importance of quality of life dimensions between people with a disability and people without a disability.MethodsAn online survey was developed and administered Australia wide. The first sample (n = 410) comprised adults (aged ≥ 18 years) with a disability (n = 208) and family carers of person/s with a disability who were asked to respond on behalf of the person with a disability (n = 202). The second sample included adults without disability (n = 443). Respondents were asked to rank the importance of 12 quality of life dimensions extracted from the content of established preference-based quality of life measures (EQ-5D, AQoL and ASCOT).ResultsPeople with a disability placed relatively higher importance on broader quality of life dimensions (e.g. Control, Independence, Self-care) relative to health status focused dimensions (e.g. Vision, Hearing, Physical mobility). This distinction was less differentiable for those ‘without a disability’. The biggest differences in ranked importance of dimensions were in: Vision (‘with disability’ = 10th, ‘without disability’ = 4th), Self-care (‘with disability’ = 3rd, ‘without disability’ = 7th) and Mental well-being (‘with disability’ = 6th, ‘without disability’ = 2nd).ConclusionsThe relative importance of quality of life dimensions for people with a disability differs to people without a disability. Quality of life is a key outcome for economic evaluation and for assessing the impact of disability care policy and practice in Australia and internationally. It is important that the effectiveness of interventions is measured and valued in ways which are fully reflective of the quality of life preferences of people with a disability.

Valuation study for a preference-based quality of life measure for dental caries (Dental Caries Utility Index - DCUI) among Australian adolescents - study protocol

IntroductionA new health state classification system has been developed for dental caries - Dental Caries Utility Index (DCUI) to facilitate the assessment of oral health interventions in the cost-utility analysis...

A hybrid modelling approach for eliciting health state preferences: the Portuguese EQ-5D-5L value set

The EQ-5D is a generic preference-based quality of life measure considered useful for supporting clinical and policy decisions by providing utility values that can easily be converted into quality-adjusted life years to be integrated in cost-utility economic evaluations. Although the three-level classification system of the EuroQol questionnaire (EQ-5D-3L) is still the most popular preference-based instrument used worldwide, several studies reported a ceiling effect on this version, especially in healthy and/or young individuals. In 2009, the EuroQol Group introduced a five-level EQ-5D, which expands the descriptive system from three to five levels within the same five dimensions. For this version to be used in health economic evaluation, societal values need to be assigned to the 3125 health states generated by this instrument. The aims of this study were to elicit the EQ-5D-5L health state preferences from the general Portuguese population and to derive the Portuguese value set for the EQ-5D-5L. A representative sample of the Portuguese general population aged above 18years was stratified by age and gender (n = 1451). Between October 2015 and July 2016, 28 interviewers carried out a series of 1-h-long computer-assisted personal interviews following the EuroQol Valuation Technology protocol. Each interview included the valuation of ten health states using the composite time trade-off (cTTO) and seven pairs of discrete choice experiments (DCEs). A standardized tool for quality control was used to assess the quality of the data as well as direct supervision and cross-examination of 10% of the global sample size. Data from both cTTO and DCE valuation tasks were modelled using a censored heteroskedastic hybrid model. Interviewers complied with the quality control protocol in providing high-quality valuation data. The hybrid econometric model had consistent and significant parameters. The derived societal values for the Portuguese population ranged from -0.603 to 1. This study provided the Portuguese value set for the EQ-5D-5L on the basis of a hybrid econometric model using cTTO and DCE data. These results represent the preferences of the Portuguese population and are recommended to inform health decision-making in Portugal.

Producing a preference-based quality of life measure for people with Duchenne muscular dystrophy: a mixed-methods study protocol

IntroductionPreference-based measures (PBMs) of health-related quality of life (HRQoL) are used to generate quality-adjusted life years, which are necessary for cost-effectiveness evaluations of health interventions via cost–utility analysis. These measures...

Assessment of the construct validity and responsiveness of preference-based quality of life measures in people with Parkinson’s: a systematic review

Generic preference-based quality of life (PbQoL) measures are sometimes criticized for being insensitive or failing to capture important aspects of quality of life (QoL) in specific populations. The objective of this study was to systematically review and assess the construct validity and responsiveness of PbQoL measures in Parkinson's. Ten databases were systematically searched up to July 2015. Studies were included if a PbQoL instrument along with a common Parkinson's clinical or QoL measure was used, and the utility values were reported. The PbQoL instruments were assessed for construct validity (discriminant and convergent validity) and responsiveness. Twenty-three of 2758 studies were included, of which the majority evidence was for EQ-5D. Overall good evidence of discriminant validity was demonstrated in the Health Utility Index (HUI)-3, EQ-5D-5L, EQ-5D-3L, 15D, HUI-2, and Disability and Distress Index (DDI). Nevertheless, HUI-2 and EQ-5D-3L were shown to be less sensitive among patients with mild Parkinson's. Moderate to strong correlations were shown between the PbQoL measures (EQ-5D-3L, EQ-5D-5L, 15D, DDI, and HUI-II) and Parkinson's-specific measures. Twelve studies provided evidence for the assessment of responsiveness of EQ-5D-3L and one study for 15D, among which six studies reached inconsistent results between EQ-5D-3L and the Parkinson's-specific measures in measuring the change overtime. The construct validity of the PbQoL measures was generally good, but there are concerns regarding their responsiveness to change. In Parkinson's, the inclusion of a Parkinson's-specific QoL measure or a generic but broader scoped mental and well-being focused measure to incorporate aspects not included in the common PbQoL measures is recommended.

Measuring quality of life in children with speech and language difficulties: a systematic review of existing approaches.

Children's and adolescent's speech and language difficulties (SaLD) can affect various domains of quality of life (QoL), and speech and language therapy interventions are critical to improving QoL. Systematically measuring QoL outcomes in this population is highly complex due to factors such as heterogeneity in impairments and differing targets during intervention. However, measurements of QoL are increasingly required by healthcare commissioners and policy-makers to inform resource allocation. To review the use of QoL measures in research involving children (age ≤ 18 years) with SaLD. A systematic review was undertaken. A systematic search across various databases was performed. Information on the methodological details of each relevant study, along with descriptions of the QoL measures employed, were extracted into standardized data extraction forms. Findings were discussed in a narrative synthesis. Twenty-one relevant studies were identified that deal with a range of subpopulations of children with SaLD. For the most part, generic QoL measures were used, although there was little convergence on the type of QoL measures employed throughout the literature. Five studies utilized preference-based QoL measures, including the 16D/17D, HUI3, EQ-5D and QWB-SA. Of these measures, the HUI3 demonstrated the most promising discriminant validity, although the preference weights for this measure were generated with adults. QoL among children with SaLD is not yet being captured in a systematic way. The HUI3 measure appears to show some promise for generating relevant preference-based QoL estimates, although further testing of the measure is required.

Sex, race, and the adverse effects of social stigma vs. other quality of life factors among primary care patients with moderate to severe obesity.

Patients with obesity face widespread social bias, but the importance of this social stigma to patients relative to other quality of life (QOL) factors is unclear. Our aim was to examine the importance of obesity-related social stigma relative to other QOL factors on reducing patients' overall well-being. We used a cross-sectional telephone interview. The study was conducted at four diverse primary care practices in Greater Boston. Three hundred and thirty-seven primary care patients aged 18-65 years and with a body mass index (BMI) of 35 kg/m(2) or higher participated in the study. Patients' health utility (preference-based QOL measure) was determined via responses to a series of standard gamble scenarios assessing willingness to risk death to lose various amounts of weight or to achieve perfect health. We used the Impact of Weight on Quality of Life-lite instrument to assess QOL domains specific to obesity (physical function, self-esteem, sexual life, public distress or social stigma, and work), and we examined variation in utility explained by these domains. Depending on patients' race/ethnicity, mean health utilities ranged from 0.92 to 0.99 among men and from 0.89 to 0.93 among women. After adjustment for race, BMI, and education, none of the QOL domains explained much of the variation in utility among men, except for work function among Hispanic men. In contrast, social stigma was the leading QOL contributor to utility for Caucasian women (explaining 6 % of the marginal variation beyond demographics and BMI). In contrast, sexual function was the most important contributor among African American women (3 % marginal variation), and work life was most important among Hispanic women (> 20 % in variation). Lower scores in one domain did not always translate into lower well-being. Moreover, QOL summary scores often explained less of the variation than some individual domains. Obesity-related social stigma had disproportionate adverse effects on Caucasian women patients' well-being, whereas weight-related impairment in work function was particularly important among Hispanic patients and impaired sexual function was important to diminished well-being among African American women although its impact appeared modest.

Measuring quality of life in mental health: Are we asking the right questions?

Measuring quality-adjusted-life years using generic preference-based quality of life measures is common practice when evaluating health interventions. However, there are concerns that measures in common use, such as the EQ-5D and SF-6D, focus overly on physical health and therefore may not be appropriate for measuring quality of life for people with mental health problems. The aim of this research was to identify the domains of quality of life that are important to people with mental health problems in order to assess the content validity of these generic measures. Qualitative semi-structured interviews were conducted with 19 people, recruited from UK mental health services, with a broad range of mental health problems at varying levels of severity. This complemented a previous systematic review and thematic synthesis of qualitative studies on the same topic. Seven domains important to quality of life for people with mental health problems were identified: well-being and ill-being; relationships and a sense of belonging; activity; self-perception; autonomy, hope and hopelessness; and physical health. These were consistent with the systematic review, with the addition of physical health as a domain, and revealed a differing emphasis on the positive and negative aspects of quality of life according to the severity of the mental health problems. We conclude that the content of existing generic preference-based measures of health do not cover this domain space well. Additionally, because people may experience substantial improvements in their quality of life without registering on the positive end of a quality of life scale, it is important that the full spectrum of negative through to positive aspects of each domain are included in any quality of life measure.

Quality of life data from EQ-5D for evidence-based health service practice in dialysis care

Background Hemodialysis (HD) and peritoneal dialysis (PD) are therapeutic options for patients with end-stage-renal-disease (ESRD), if transplantation is not available. Mortality rates for HD and PD are similar, while PD is generally the less costly alternative. Percentage of HD and PD shows considerable variability between high income countries (for PD from 5-7% in Germany and Switzerland up to 19-24% in the UK and Scandinavia). Patient reported outcomes, such as quality of life (QOL), can provide complementary evidence for planning of patient oriented dialysis services. Profile instruments (e.g. SF36, KDQOL) show no consistent QOL differences between HD and PD. However, single index preference-based QOL measures (such as EQ-5D), may add new information and are useful for later health economic evaluations. We aimed to collect current evidence for QOL of ESRD patients as measured with EQ-5D.

Economic and Humanistic Burden of External Genital Warts

External genital warts (EGW) are a sexually transmitted infection caused by various strains of human papillomavirus (HPV). Several studies have described the direct and indirect costs of EGW, while others have reported on the burden of EGW in terms of the impact on the quality of life (QOL) of patients. The arrival of a quadrivalent HPV vaccine that protects against both cervical cancer and EGW requires a proper understanding of the impact of vaccines on costs and QOL. Using pre-defined search terms and inclusion/exclusion criteria, we performed a systematic review of the economic and humanistic burden of EGW. The focus of our review was on literature describing the direct and indirect costs of EGW per episode of care (EoC) or per year, as well as the impact of EGW on disease-specific, generic, or preference-based QOL measures. We also reviewed the literature on the national economic burden of EGW from the perspectives of different countries. Other aspects of EGW management that can inform economic modelling studies, such as length of EoC, number of physician visits and indirect costs, were also explored. Our review sheds light on the high economic and humanistic burden of EGW and important differences in the costs between men and women, as well as the differences in health resource utilization and costs across countries. Our study also highlights the dearth of information on the impact of EGW on the QOL and productivity of patients.

Future Directions in Dermatology Quality of Life Measures

Within the last few decades, outcomes research, and in particular quality of life (QoL) outcomes research, has become integrated into clinical and research practices. QoL outcomes are important to dermatology, because many diseases carry significant psychosocial burdens and morbidity from appearance and symptoms with few cases of mortality. In this article, the authors discuss the future directions in QoL. Important areas are the determination, clinical significance and interpretation of measured QoL values. Additionally, the development of proxies for preference-based QoL measures and modules for health status QoL measures are discussed.

Systematic reviews and economic evaluations conducted for the National Institute for Health and Clinical Excellence in the United Kingdom: A game of two halves?

Decision analytic models, as used in economic evaluations, require data on several clinical parameters. The gold standard approach is to conduct a systematic review of the relevant clinical literature, although reviews of economic evaluations indicate that this is rarely done. Technology appraisals for the National Institute for Health and Clinical Excellence (NICE), which are fully funded, represent the best case scenario for the close integration of economic evaluations and systematic reviews. The objective of this study was to assess the extent to which the systematic review of the clinical literature informs the economic evaluation in NICE technology appraisals. All NICE technology assessment reports (TARs) published between January 2003 and July 2006 were considered. Data were abstracted on the TAR topics, the primary measure of clinical effectiveness, the approach to pooling in the clinical review, the measure of economic benefit and the use, or non-use, of the systematic review in the economic evaluation. Forty-one TARs were published in the period studied, all of which contained a systematic review. Most of the economic evaluations (85 percent) were cost-utility analyses, reflecting NICE's guidelines for economic evaluation. In seventeen cases, the clinical data were not pooled in the review, owing to heterogeneity in the clinical data or the limited number of studies. In these cases, the economists used alternative approaches for estimating the key effectiveness parameter in the model. The results of the review (when pooled) were always used when the primary clinical effectiveness measure corresponded with the measure of economic benefit (e.g., survival). However, because preference-based quality of life measures are rarely included in clinical trials, the results of the systematic review were never directly used in the cost-utility analyses. Nevertheless, the outputs of the systematic review were used when the data were useful in estimating components of the quality-adjusted life-year (QALY) (e.g., the life-years gained, or the frequencies of health states to which QALYs could be assigned). Problems occurred mainly when the clinical data were not pooled, or when the measure of clinical benefit could not be converted into health states to which QALYs could be assigned. Economic evaluations can benefit from systematic reviews of the clinical literature. However, such reviews are not a panacea for conducting a good economic evaluation. Much of the relevant data for estimating QALYs are not contained in such reviews and the chosen method for summarizing the clinical data may inhibit the assessment of economic benefit. Problems would be reduced if those undertaking the technology assessments discussed the data requirements for the economic model at an early stage.

Item-Based versus Subscale-Based Mappings from the SF-36 to a Preference-Based Quality of Life Measure

Objective Algorithms for mapping descriptive measures of health status into preference-based measures are now widely available and their application in economic evaluation is increasingly commonplace. Existing algorithms make use of scale, subscale, or item scores on descriptive measures. Item-based algorithms entail fewer restrictions than their scale or subscale-based equivalents but are subject to problems in estimation and application. The objective of the present study is to quantify any loss of predictive validity associated with using subscale or scale scores (rather than item scores) to derive conversion algorithms. Methods Multiple linear regression methods to derive item-based, subscale-based, and scale-based algorithms for mapping SF-36 data into Assessment of Quality of Life (AQoL) utility scores in a stratified sample of persons aged more than 16 years and resident in Victoria, Australia. The theoretical consistency and predictive validity of competingalgorithms is evaluated against criteria reflecting the intended use of predicted utility scores. Results Three mappings were suitable for between-group comparisons. There was no discernible increase in error associated with a move from the item-based mapping to either the subscale- or scale-based mapping. Conclusion Our results do not support the hypothesis that fewer restrictions on functional form necessarily result in a lower magnitude of error when predicting between-group differences. Rather, it appears that the subscale-based mapping offers a good compromise—requiring fewer restrictions on the form of the relationship between SF-36 responses and the AQoL utility score than the scale-based mapping and permitting a more efficient use of SF-36 data than the item-based mapping.

Preference-Based Quality of Life Measures in People with Visual Impairment

The use of preference-based measures of quality of life represents the application of principles of decision theory and welfare economics to the measurement of health-related concepts. In this Perspective, we present the theoretical basis of preference-based measures in the assessment of the impact of vision-related disease on quality of life and their role in cost-effectiveness analysis. We discuss the use of the standard gamble and time trade-off in eliciting utilities and the limitations of both methods. Scaling issues related to utility are discussed, in particular the reasons for use of the "policy scale" (i.e., a scale where utilities are anchored at 1.0 for perfect health and 0 as death). This is contrasted with the use of the "vision-truncated scale" (i.e., a scale with 1.0 representing perfect vision and 0 being death), which is commonly used in assessment of vision-related utilities. We discuss problematic aspects of using the truncated scale in conducting cost-effectiveness research for vision-related disease, and provide a theoretical and empirical discussion of these limitations. In particular, we point out how these results raise questions concerning the conceptual relationship between vision- and health-related quality of life. Finally, we present the results of previous cross-cultural and trans-national studies of vision-related quality of life to demonstrate how utility studies might provide insight into the meaning of disease across cultures.

Preference-Based Quality of Life in Patients With Cerebral Aneurysms

Functional outcome scales are typically used to measure quality of life (QOL) and outcomes in patients with cerebral aneurysms; however, these instruments only examine a limited number of domains that contribute to QOL. An alternative are preference-based QOL methods, which integrate all factors contributing to QOL and provide a comprehensive individualized measure of how patients value their current health state. An additional advantage of preference-based QOL values is that they can be incorporated into decision analyses and cost-effectiveness analyses. We used 4 preference-based QOL methods to measure QOL in 176 outpatients with cerebral aneurysms: (1) standard gamble; (2) time trade-off; (3) visual analogue scale; and (4) willingness to pay. We measured functional status with the Glasgow Outcome Scale (GOS), Rankin Scale, and Barthel Index. We then built multivariate linear regression models to examine the relationships between preference-based QOL, functional status, and patient characteristics. Preference-based QOL was moderately diminished in the aneurysm patients. Mean values were: standard gamble, 0.78; time trade-off, 0.79; visual analogue scale, 0.67; and willingness to pay, 121,000 dollars. Preference-based QOL was not well-explained by functional status or patient characteristics, as shown by regression models that accounted for <15% of the variation in preference-based QOL (R2<0.15). Preference-based QOL instruments capture components of QOL in patients with cerebral aneurysms not assessed by functional status measures or patient characteristics. Studies of patients with cerebral aneurysms should consider incorporating preference-based QOL measures for a fuller evaluation of the impact of aneurysmal disease and its treatment on QOL.