Health values of adolescents with cystic fibrosis

The estimation of health state utility values in rare diseases: do the approaches in submissions for NICE technology appraisals reflect the existing literature? A scoping review

BACKGROUND

Rare diseases negatively impact patients' quality of life, but the estimation of health state utility values (HSUVs) in research studies and cost-utility models for health technology assessment is challenging.

OBJECTIVES

This study compared the methods for estimating the HSUVs included in manufacturers' submissions of orphan drugs to the National Institute for Health and Care Excellence (NICE) with those of published studies addressing the same rare diseases to understand whether manufacturers fully exploited the existing literature in developing their economic models.

METHODS

All NICE Technology Appraisal (TA) and Highly Specialized Technologies (HST) guidance documents of non-cancer European Medicines Agency (EMA) orphan medicinal products were reviewed and compared with any published primary studies, retrieved via PubMed until November 2020, and estimating HSUVs for the same conditions addressed in manufacturers' submissions.

RESULTS

We identified 22 NICE TA/HST appraisal reports addressing 19 different rare diseases. Sixteen reports presented original HSUVs estimated using EQ-5D or Health Utility Index (n = 12), direct methods (n = 2) or mapping (n = 2), while the other six included values obtained from the literature only. In parallel, we identified 111 published studies: 86.6% used preference-based measures (mainly EQ-5D, 60.7%), 12.5% direct techniques, and 2.7% mapping. The collection of values from non-patient populations (using 'vignettes') was more frequent in manufacturers' submissions than in the literature (22.7% vs. 8.0%).

CONCLUSIONS

The agreement on methodological choices between manufacturers' submissions and published literature was only partial. More efforts should be made by manufacturers to accurately reflect the academic literature and its methodological recommendations in orphan drugs submissions.

Estimating an EQ-5D-Y-3L Value Set for Indonesia by Mapping the DCE onto TTO Values

BACKGROUND AND OBJECTIVES

Methods for estimating health values in adult populations are well developed, but lag behind in children. The EuroQol standard protocol to arrive at value sets for the youth version of the EQ-5D-Y-3L combines discrete choice experiments with ten composite time trade-off values. Whether ten composite time trade-off values are sufficient remains to be seen and this is one of the reasons the protocol allows for experimental expansion. In this study, 23 health states were administered for the composite time trade-off. This methodological research is embedded in a study aimed at generating a representative value set for EQ-5D-Y-3L in Indonesia.

METHODS

A representative sample of 1072 Indonesian adults each completed 15 discrete choice experiment choice pairs via face-to-face interviews. The discrete choice experiment responses were analysed using a mixed-logit model. To anchor the discrete choice experiment values onto the full health-dead quality-adjusted life-year scale, composite time trade-off values were separately obtained from 222 adults living in Java for 23 EQ-5D-Y-3L states. The derived latent discrete choice experiment values were mapped onto the mean observed composite time trade-off values to create a value set for the EQ-5D-Y-3L. Linear and non-linear mapping models were explored to estimate the most efficient and valid model for the value set.

RESULTS

Coefficients obtained from the choice model were consistent with the monotonic structure of the EQ-5D-Y-3L instrument. The composite time trade-off data showed non-linearity, as the values for the two worst states being evaluated were much lower than predicted by a standard linear model estimated over all composite time trade-off data. Thus, the non-linear mapping strategies with a power term outperformed the linear mapping in terms of mean absolute error. The final model gave a value range from 1.000 for full health (11111) to - 0.086 for the worst health state (33333). Values were most affected by pain/discomfort and least by self-care.

CONCLUSIONS

This article presents the first EQ-5D-Y-3L value set for Indonesia based on the stated preferences of adults asked to consider their views about a 10-year-old child. Mapping the mixed-logit discrete choice experiment model with the inclusion of a power term (without a constant) allowed us to generate a consistent value set for Indonesian youth. Our findings support the expansion of the composite time trade-off part of the EQ-5D-Y valuation study design and show that it would be wise to account for possible non-linearities in updates of the design.

Preference Elicitation Techniques Used in Valuing Children's Health-Related Quality-of-Life: A Systematic Review

BACKGROUND AND OBJECTIVES

Valuing children's health states for use in economic evaluations is globally relevant and is of particular relevance in jurisdictions where a cost-utility analysis is the preferred form of analysis for decision making. Despite this, the challenges with valuing child health mean that there are many remaining questions for debate about the approach to elicitation of values. The aim of this paper was to identify and describe the methods used to value children's health states and the specific issues that arise in the use of these methods.

METHODS

We conducted a systematic search of electronic databases to identify studies published in English since 1990 that used preference elicitation methods to value child and adolescent (under 18 years of age) health states. Eligibility criteria comprised valuation studies concerning both child-specific patient-reported outcome measures and child health states defined in other ways, and methodological studies of valuation approaches that may or may not have yielded a value set algorithm.

RESULTS

A total of 77 eligible studies were identified from which data on country setting, aims, condition (general population or clinically specific), sample size, age of respondents, the perspective that participants were asked to adopt, source of values (respondents who completed the preference elicitation tasks) and methods questions asked were extracted. Extracted data were classified and evaluated using narrative synthesis methods. The studies were classified into three groups: (1) studies comparing elicitation methods (n = 30); (2) studies comparing perspectives (n = 23); and (3) studies where no comparisons were presented (n = 26); selected studies could fall into more than one group. Overall, the studies varied considerably both in methods used and in reporting. The preference elicitation tasks included time trade-off, standard gamble, visual analogue scaling, rating/ranking, discrete choice experiments, best-worst scaling and willingness to pay elicited through a contingent valuation. Perspectives included adults' considering the health states from their own perspective, adults taking the perspective of a child (own, other, hypothetical) and a child/adolescent taking their own or the perspective of another child. There was some evidence that children gave lower values for comparable health states than did adults that adopted their own perspective or adult/parents that adopted the perspective of children.

CONCLUSIONS

Differences in reporting limited the conclusions that can be formed about which methods are most suitable for eliciting preferences for children's health and the influence of differing perspectives and values. Difficulties encountered in drawing conclusions from the data (such as lack of consensus and poor reporting making it difficult for users to choose and interpret available values) suggest that reporting guidelines are required to improve the consistency and quality of reporting of studies that value children's health using preference-based techniques.

Exploring the Issues of Valuing Child and Adolescent Health States Using a Mixed Sample of Adolescents and Adults

Preferences for child and adolescent health states used to generate health state utility values can be elicited from adults, young adults, adolescents, or combinations of these. This commentary paper provides a critical overview of issues and implications arising from valuing child and adolescent health states using a novel approach of a mixed sample of adolescents and adults. The commentary is informed by critical analysis of normative, ethical, practical and theoretical arguments in the health state valuation literature. Discussion focusses upon adolescent empowerment, understanding and psychosocial maturity; ethical concerns; elicitation tasks; perspective; and selection of sample proportions across adolescents and adults. It is argued that valuation of child and adolescent health states by both adolescents and adults could involve all participants completing the same preference elicitation task using the same perspective (e.g. time trade-off imagining they are living in the health state), and all preferences being modelled to generate a combined value set that reflects both adolescent and adult preferences. It is concluded that the valuation of child and adolescent health states by a mixed adolescent and adult sample appears feasible and has the advantage that it includes some of the population who can potentially experience the health states, thus enabling adolescents to express their views around matters that may affect them, and the population that are taxpayers and voters. However, both the relative proportion of adults and adolescents to include in a valuation sample and the elicitation technique require careful consideration.

Health utility and quality of life in pediatric liver transplant recipients

To measure HU and HRQOL in pediatric liver transplant (LT) recipients, a cross-sectional study of patient-parent dyads was conducted. Direct HU were assessed in 48 adolescents ≥12 years using SG and TTO techniques. Indirect HU were measured by Health Utility Index 2 and HUI3 for subjects ≥12 years and CHU9D for ≥7 years. Patients reported HRQOL using PedsQL™ GC and PedsQL™ TM. A total of 108 dyads participated (55.6% female; 73.2% Caucasian; 42.6% biliary atresia; 35.2% living donor; 37.0% Medicaid). Mean age at survey was 13.6 ± 3.5 years, and time from LT was 8.9 ± 4.9 years. 61.2% were on monotherapy, 25 (23.2%) had acute rejection within 3 years, and 15 (13.9%) had a biliary obstruction within 5 years. Mean indirect HU and HRQOL scores by child report were lower than norms (P < .001). LRD recipients had higher PedsQL™ GC, PedsQL™ TM, and HUI3 scores (P < .01). HU in pediatric LT recipients are lower than norms. Availability of HU scores for post-transplant health states will enable measurement of quality-adjusted life years for future comparative effectiveness studies.

Review of Valuation Methods of Preference-Based Measures of Health for Economic Evaluation in Child and Adolescent Populations: Where are We Now and Where are We Going?

Methods for measuring and valuing health benefits for economic evaluation and health technology assessment in adult populations are well developed. In contrast, methods for assessing interventions for child and adolescent populations lack detailed guidelines, particularly regarding the valuation of health and quality of life in these age groups. This paper critically examines the methodological considerations involved in the valuation of child- and adolescent-specific health-related quality of life by existing preference-based measures. It also describes the methodological choices made in the valuation of existing generic preference-based measures developed with and/or applied in child and adolescent populations: AHUM, AQoL-6D, CHU9D, EQ-5D-Y, HUI2, HUI3, QWB, 16D and 17D. The approaches used to value existing child- and adolescent-specific generic preference-based measures vary considerably. While the choice of whose preferences and which perspective to use is a matter of normative debate and ultimately for decision by reimbursement agencies and policy makers, greater research around these issues would be informative and would enrich these discussions. Research can also inform the other methodological choices required in the valuation of child and adolescent health states. Gaps in research evidence are identified around the impact of the child described in health state valuation exercises undertaken by adults, including the possibility of informed preferences; the appropriateness and acceptability of valuation tasks for adolescents, in particular tasks involving the state 'dead'; anchoring of adolescent preferences; and the generation and use of combined adult and adolescent preferences.

Health State Utility Data in Cystic Fibrosis: A Systematic Review

INTRODUCTION

Cystic fibrosis (CF) is a life-limiting, hereditable condition, with the highest prevalence in Europe. CF treatments have led to improvements in clinical symptoms, disease management and decelerated disease progression. However, little is known about the health state utility (HSU) associated with CF disease states, adverse events, and changes in disease severity. Although HSU data have contributed to existing health economic modelling studies, a lack of such data have been highlighted. This systematic review aims to provide a summary of HSU-related research in CF and highlight related research gaps.

METHODS

Online searches were performed in six databases and studies in any of the following categories were included: (1) estimation of HSUs in CF; (2) mapping studies between patient-reported outcome measures (PROMs) and HSUs; (3) economic evaluations on the management of CF that report primary HSU data; and (4) any CF clinical trial that reported HSU as an outcome.

RESULTS

A total of 17 studies were reviewed, of which 12 provided HSU values for specific CF populations. The remaining five articles provided HSU data that were broken down by CF relevant health states, including lung transplantations, pulmonary exacerbation (PEx) events and forced expiratory volume in 1 s (FEV₁).

CONCLUSION

Current HSU data in CF are limited and there is considerable scope for further research, both in providing HSU values for CF and in investigating methods for HSU elicitation/evaluation in CF populations.

Valuation of EuroQol Five-Dimensional Questionnaire, Youth Version (EQ-5D-Y) and EuroQol Five-Dimensional Questionnaire, Three-Level Version (EQ-5D-3L) Health States: The Impact of Wording and Perspective

BACKGROUND

Valuations of health states were affected by the wording of the two instruments (EQ-5D-3L and EQ-5D-Y) and by the perspective taken (child or adult).

OBJECTIVES

There is a growing demand for value sets for the EQ-5D-Y (EQ-5D instrument for younger populations). Given the similarities between EQ-5D-Y and EQ-5D-3L, we investigated whether valuations of health states were affected by the differences in wording between the two instruments and by the perspective taken in the valuation exercise (child or adult).

STUDY DESIGN

Respondents were randomly assigned to EQ-5D-3L or EQ-5D-Y (instrument) and further into two groups that either valued health states for an adult or for a 10-year-old child (perspective). The valuation tasks were composite time trade-off (C-TTO) and discrete choice experiments (DCE), including comparisons with death (DCE + death). Members of the adult general population in four countries (Germany, Netherlands, Spain, England) participated in computer-assisted personal interviews.

METHODS

Two-way multivariate analysis of variance (MANOVA) and post hoc tests were used to compare C-TTO responses and chi-square tests were conducted to compare DCE + death valuations.

RESULTS

A significant interaction effect between instrument and perspective for C-TTO responses was found. Significant differences by perspective (adult and child) occurred only for the EQ-5D-3L. Significant differences in values between instruments (EQ-5D-3L and EQ-5D-Y) occurred only for the adult perspective. Both significant results were confirmed by the DCE + death results. When comparing EQ-5D-3L for adult perspective and EQ-5D-Y for child perspective, values were also significantly different.

CONCLUSIONS

The results identified an interaction effect between wording of the instrument and perspective on elicited values, suggesting that current EQ-5D-3L value sets should not be employed to assign values to EQ-5D-Y health states.

The cost-effectiveness of palivizumab in infants with cystic fibrosis in the Canadian setting: A decision analysis model

BACKGROUND

Children with cystic fibrosis (CF) are at higher risk of severe respiratory syncytial virus (RSV) infection, which can lead to a decline in lung function. A monoclonal antibody, palivizumab (PMB), effectively prevents RSV hospitalizations; however, the high cost of PMB, approximately C$10,000 per patient per RSV season, limits its widespread use. We assess the cost-effectiveness of PMB prophylaxis in CF children less than 2 y of age from the Canadian healthcare payer's perspective.

METHODS

In 2014, a Markov cohort model of CF disease and infant RSV infections in the Canadian setting was developed based on literature data. Infants were treated with monthly PMB injections over the 5-month RSV season. Lifetime health outcomes, quality-adjusted life years (QALYs) and 2013 $CAD costs, discounted at 5%, were estimated. Findings are summarized as incremental cost-effectiveness ratios (ICERs) and budget impact. Deterministic sensitivity analysis was conducted to assess parameter uncertainty.

RESULTS

Implementation of a hypothetical Canadian RSV prophylaxis program resulted in ICERs of C$652,560 (all CF infants) and C$157,332 (high-risk CF infants) per QALY gained and an annual budget impact of C$1,400,000 (all CF infants) and C$285,000 (high-risk CF infants). The analysis was highly sensitive to the probability of severe RSV, the degree of lung deterioration following infection, and the cost of PMB.

CONCLUSIONS

Our results suggest PMB is not cost-effective in Canada by commonly used thresholds. However, given the rarity of CF and relatively small budget impact, consideration may be given for the selective use of PMB for immunoprophylaxis of RSV in high-risk CF infants on a case-by-case scenario basis.

Reliability, Validity, and Feasibility of Direct Elicitation of Children's Preferences for Health States

BACKGROUND

Children's preferences for health states represent an important perspective when comparing the value of alternative health care interventions related to pediatric medicine, and are fundamental to comparative effectiveness research. However, there is debate over whether these preference data can be collected and used.

PURPOSE

The purpose of this study was to establish psychometric properties of eliciting preferences for health states from children using direct methods.

DATA SOURCES

Ovid Medline, PsycINFO, Scopus, EconLit.

STUDY SELECTION

English studies, published after 1990, were identified using Medical Subject Headings or keywords. Results were reviewed to confirm that the study was based on: 1) a sample of children, and 2) preferences for health states.

DATA EXTRACTION

Standardized data collection forms were used to record the preference elicitation method used, and any reported evidence regarding the validity, reliability, or feasibility of the method.

DATA SYNTHESIS

Twenty-six studies were ultimately included in the analysis. The standard gamble and time tradeoff were the most commonly reported direct preference elicitation methods. Seven studies reported validity, four reported reliability, and nine reported feasibility. Of the validity reports, construct validity was assessed most often. Reliability reports typically involved interclass correlation coefficient. For feasibility, four studies reported completion rates.

LIMITATIONS

The search was limited to four databases and restricted to English studies published after 1990. Only evidence available in published studies were considered; measurement properties may have been tested in pilot or pre-studies but were not published, and are not included in this review.

CONCLUSION

The few studies found through this systematic review demonstrate that there is little empirical evidence on which to judge the use of direct preference elicitation methods with children regarding health states.

Validity of a condition specific outcome measure for fragile X syndrome: the Aberrant Behaviour Checklist-utility index

BACKGROUND

The purpose of this study was to assess the construct validity of the Aberrant Behaviour Checklist-utility index (ABC-UI) by examining the relationship between healthcare resource utilisation by patients with fragile X syndrome (FXS) as well as burden experienced by their caregivers.

METHOD

In 2011, a total of 350 US caregivers of individuals with FXS completed a questionnaire that captured information on FXS-related burden as well as the ABC-Community. Using the ABC-UI, a condition-specific outcome measure derived from the ABC-Community, five utility index categories were created: very low (0.00-0.33); low (0.34-0.66); moderate (0.67-0.77); high (0.78-0.89); and very high (0.90-1.00). Multivariable regression models examined the association between the utility value and nine burden-related outcomes.

RESULTS

Approximately 2% of individuals with FXS were in the very low utility index category, 31% low, 27% moderate, 38% high and 3% very high. The median utility value was 0.74. Women with FXS and adults 18 years and older had higher values. Regression results indicate that individuals with higher utility values were more likely to have fewer specialist visits, use fewer prescription medications, need fewer hours of unpaid caregiving, inflict fewer caregiver injuries and have caregivers with fewer mental health provider visits.

CONCLUSIONS

The ABC-UI appears to function well as condition-specific outcome measure, and as an indicator of health-related quality-of-life and economic burden in individuals with FXS. Among patients with FXS in the US and their caregivers, significant differences in health care resource utilisation and burden exist across health state utility categories.

Bilateral Hallux Valgus: A Utility Outcome Score Assessment

Hallux valgus is the most common forefoot problem in adults. Although it can cause considerable disability and affect the quality of life of those affected, many patients seek medical attention because of cosmetic concerns. Our aim was to objectively measure the perceived health burden of living with bilateral hallux valgus. Previously validated utility outcome measures, including the visual analog scale, time trade-off, and standard gamble tests, were used to quantify the health burden for single-eye blindness, double-eye blindness, and bilateral hallux valgus in 103 healthy subjects using an online survey. The Student t test and linear regression analysis were used for statistical analysis. The mean visual analog scale, time trade-off, and standard gamble scores for bilateral hallux valgus were 0.86 ± 1.6, 0.95 ± 0.5, and 0.95 ± 0.14, respectively. These were significantly greater than the utility scores for single-eye and double-eye blindness (p < .05). Age, gender, race, income, and education were not statistically significant independent predictors of the utility scores for hallux valgus. In conclusion, we have objectively demonstrated the effect of living with bilateral hallux valgus deformities. Our sample population reported being willing to undergo a procedure with a 5% mortality rate and sacrifice 1.8 years of life to attain perfect health and avoid the bilateral hallux valgus health state. Our findings will guide us in counseling our patients and understanding how they perceive their foot deformity.

Impact of pulmonary exacerbations and lung function on generic health-related quality of life in patients with cystic fibrosis

BACKGROUND

The analysis aimed to examine the impact of pulmonary exacerbations (PEs) and lung function on generic measures of HRQL in patients with cystic fibrosis (CF) using trial-based data.

METHODS

In a 48-week randomized, placebo-controlled study of ivacaftor in patients ≥12 years with CF and a G551D-CFTR mutation the relationship between PEs, PE-related hospitalizations and percent predicted forced expiratory volume in one second (ppFEV1) with EQ-5D measures (index and visual analog scale [VAS]) was examined in post-hoc analyses. Multivariate mixed-effects models were employed to describe the association of PEs, PE-related hospitalizations, and ppFEV1 on EQ-5D measures.

RESULTS

One hundred sixty one patients (age: mean 25.5 [SD 9.5] years; baseline ppFEV1: 63.6 [16.4]) contributed 1,214 observations (ppFEV1: no lung dysfunction [n = 157], mild [n = 419], moderate [n = 572], severe [n = 66]). Problems were most frequently reported on pain/discomfort, anxiety/depression, and usual activities EQ-5D items. The mean (SE) EQ-5D index nominally decreased (worsened) with worsening severity of lung dysfunction (P = 0.070): 0.931 (0.023); mild: 0.923 (0.021); moderate: 0.904 (0.018); severe: 0.870 (0.020). 146 PEs were experienced by 72 patients, including 52 PEs (35.6 %) that required hospitalization. Mean EQ-5D index and VAS scores were lowest (worst) within 1 week (before or after PE start) for PEs requiring hospitalization. Pulmonary exacerbations, PE-related hospitalizations, and ppFEV1 were significant predictors of EQ-5D index and VAS.

CONCLUSIONS

In a clinical study of patients with CF (≥12 years of age and a G551D-CFTR mutation), PEs, primarily those requiring hospitalization, were associated with low EQ-5D index and VAS scores. The impact of ppFEV1 was relatively smaller. Reducing PEs, in particular those requiring hospitalization, would likely improve HRQL among these patients.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00909532 ; URL: clinicaltrials.gov, May 26, 2009.

Parental Perceptions of Quality of Life in Children on Long-Term Ventilation at Home as Compared to Enterostomy Tubes

Objective

Health related quality of life (HRQL) of children using medical technology at home is largely unknown. Our aim was to examine the HRQL in children on long-term ventilation at home (LTHV) in comparison to a cohort using an enterostomy tube.

Study Design

Participants were divided into three groups: 1) LTHV without an enterostomy tube (LTHV cohort); 2) Enterostomy tube (GT cohort); 3) LTHV with an enterostomy tube (LTHV+GT cohort). Caregivers of children ≥ 5 years and followed at SickKids, Toronto, Canada, completed three questionnaires: Health Utilities Index 2/3 (HUI2/3), Caregiver Priorities Caregiver Health Index (CPCHILD), and the Paediatric Quality of Life Inventory (PedsQL). The primary outcome was the difference in utility (HUI2/3) scores between the cohorts.

Results

One hundred and nineteen children were enrolled; 47 in the LTHV cohort, 44 in the GT cohort, and 28 in the LTHV+GT cohort. In univariate analysis, HUI2 mean (SE) scores were lowest for the GT cohort, 0.4 (0.04) followed by the LTHV+GT, 0.42 (0.05) and then the LTHV cohort, 0.7 (0.04), p = 0.001. A similar trend was seen for the HUI3 mean (SE) scores: GT cohort, 0.1 (0.06), followed by the LTHV +GT cohort, 0.2 (0.08) and then the LTHV cohort, 0.5 (0.06), p = 0.0001. Technology cohort, nursing hours and the severity of health care needs predicted HRQL as measured by the HUI2/3.

Conclusion

The HRQL of these children is low. Children on LTHV had higher HRQL than children using enterostomy tubes. Further work is needed to identify modifiable factors that can improve HRQL.

Valuing Child Health Utility 9D Health States with Young Adults: Insights from a Time Trade Off Study

OBJECTIVES

In contrast to the proliferation of studies incorporating health state values from adults of all ages, relatively few studies have reported upon the application of the time trade off (TTO) approach to generate health state values from populations of younger adults. This study sought to employ a conventional TTO approach to obtain values for a selection of Child Health Utility 9D (CHU9D) health states from a sample of young adults aged 18-29 years and to compare with the values generated from application of the original UK adult standard gamble scoring algorithm and the Australian adolescent scoring algorithm.

METHODS

A convenience sample of Flinders University undergraduate students aged 18-29 years were invited to participate in an interviewer administered conventional TTO task to value a series of five CHU9D health impairment states using the widely used variant developed by the York EQ-5D team.

RESULTS

A total of 152 students within the target age range were approached to participate in the study of whom n = 38 consented to participate, giving an overall participation rate of 25%. With the exception of one health state, the mean TTO values were consistently lower than those generated from application of the original scoring algorithm for the CHU9D elicited with adults of all ages. A significant proportion of participants (n = 17, 45%) considered the most severe CHU9D (PITS) state to be worse than death.

CONCLUSIONS

This study adds to a growing body of evidence indicating that the values attached to identical health states are typically lower for younger people in comparison with adults of all ages and dependent upon the elicitation method utilised. The values obtained are applicable for re-scaling raw CHU9D health state values obtained from younger adolescent samples using profile case best-worst scaling.

A Review of the Development and Application of Generic Multi-Attribute Utility Instruments for Paediatric Populations

Multi-attribute utility instruments (MAUIs) are increasingly being used as a means of quantifying utility for the calculation of quality-adjusted life-years within the context of cost utility analysis. Traditionally, MAUIs have been developed and applied in adult populations. However, increasingly, researchers in health economics and other disciplines are recognising the importance of the measurement and valuation of health in both children and adolescents. Presently, there are nine generic MAUIs available internationally that have been used in paediatric populations: the Quality of Well-Being Scale (QWB), the Health Utility Index Mark 2 (HUI2), the HUI3, the Sixteen-dimensional measure of health-related quality of life (HRQoL) (16D), the Seventeen-dimensional measure of HRQoL (17D), the Assessment of Quality of Life 6-Dimension (AQoL-6D) Adolescent, the Child Health Utility 9D (CHU9D), the EQ-5D Youth version (EQ-5D-Y) and the Adolescent Health Utility Measure (AHUM). This paper critically reviews the development and application of the above nine MAUIs and discusses the specific challenges of health utility measurement in children and adolescents. Areas for further research relating to the development and application of generic MAUIs in paediatric populations are highlighted.

The cost effectiveness of dry powder antibiotics for the treatment of Pseudomonas aeruginosa in patients with cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) affects over 9,000 people in the UK and limits life expectancy. CF patients are susceptible to lung infections, most commonly Pseudomonas aeruginosa. Once infection is established, patients require lifetime treatment using nebulised antibiotics. Newer dry powder formulations of antibiotics may reduce treatment burden and improve compliance.

OBJECTIVE

Our objective was to evaluate the cost effectiveness of (i) colistimethate sodium dry powder for inhalation (DPI) and (ii) tobramycin DPI versus nebulised tobramycin for the treatment of chronic P. aeruginosa lung infection in patients with CF from the perspective of the National Health Service (NHS) and Personal Social Services (PSS).

METHODS

We developed a state transition model based on transitions between three strata of lung function measured in terms of forced expiratory volume in 1 second (FEV1) % predicted. Additional health states representing post-lung transplantation and dead are also modelled. The model structure was informed by systematic reviews of evidence concerning the plausibility of potential relationships between intermediate endpoints and final outcomes. The model assumes that treatment impacts on FEV1 trajectory, which manifest as changes in health-related quality of life. No survival benefit is assumed due to the absence of robust quantifiable evidence. Model parameters were informed by patient-level and aggregate data from two randomised controlled trials together with the best available evidence from the literature. Resource use and costs associated with drug acquisition, the management of exacerbations and reduced nebuliser maintenance were drawn from reference sources and expert opinion. Costs were valued at 2011/2012 prices. Costs and health outcomes were discounted at a rate of 3.5 %. Simple and probabilistic sensitivity analyses were undertaken, including additional analyses of Patient Access Scheme (PAS) price discounts offered by the manufacturers of both DPI products.

RESULTS

Colistimethate sodium DPI is expected to produce fewer quality-adjusted life-years (QALYs) than nebulised tobramycin. Based on its list price, colistimethate sodium DPI is expected to be dominated by nebulised tobramycin. When the PAS is incorporated, the incremental cost-effectiveness ratio (ICER) for colistimethate sodium DPI versus nebulised tobramycin is expected to be approximately £288,600 saved per QALY lost. Based on its current list price, the ICER for tobramycin DPI versus nebulised tobramycin is expected to be approximately £124,000 per QALY gained. When the proposed PAS is included, tobramycin DPI is expected to dominate nebulised tobramycin.

CONCLUSIONS

Under their list prices, neither DPI product is likely to represent good value for money for the NHS given current cost-effectiveness thresholds. The PAS discounts have a significant impact upon the economic attractiveness of both DPI products compared against nebulised tobramycin. The clinical effectiveness and cost effectiveness of the DPIs against other nebulised antibiotics, such as aztreonam and inhaled colistimethate sodium, remains unclear.

Health status and health-related quality of life in a pediatric palliative care program

BACKGROUND

Children with life-threatening illnesses have unique physical and psychosocial needs that pediatric palliative care programs can address. Integrated programs strive to address these needs from the point of diagnosis through death, if needed, at the same time that curative care is provided. To better understand the variation in these needs, we assessed the health status and health-related quality of life (HRQOL) of children enrolled in an integrated pediatric palliative care program.

METHODS

A telephone survey was conducted with 98 parents whose children were enrolled in an integrated pediatric palliative care program in Florida. The Health Utilities Index (HUI) system was used to assess health status and HRQOL.

RESULTS

HUI2 attribute levels show that children have the greatest impairment with moderate-to-severe burdens related to self-care, mobility, and sensation, and the least impairment with emotion. HUI3 attribute levels show that children have the greatest impairment with moderate-to-severe burdens related to ambulation and cognition and the least impairment with hearing and emotional functioning. Mean overall HUI2 and HUI3 utility scores are 0.37 and 0.15, respectively.

CONCLUSION

Children with life-threatening illnesses in our sample had a high level of morbidity compared with those found in other HUI studies of children with acute or chronic health conditions. Not only do our results highlight severely impaired HRQOL, they also demonstrate the wide variety of health states and needs for children in integrated palliative care programs. This information can help develop strategies to encourage more providers to participate in integrated pediatric palliative care programs.

Health status in young adults two decades after pediatric liver transplantation

We conducted a cross-sectional study of patients who underwent pediatric liver transplant (LT) between 1988 and 1992 to evaluate long-term health status. Survivors completed socio-demographic, medical and Health-Related Quality of Life (HRQOL) surveys by mail including the SF-36v2, PedsQL™4.0 Generic Core Scale, PedsQL™ Cognitive Functioning Scale and PedsQL™3.0 Transplant Module. SF-36 scores were converted to SF6D-based utilities and risk factors for lower outcomes were assessed. Eighty-five of 171 patients had survived. Fifty-six were contacted with a response rate of 66%. Median age at LT was 0.86 years (IQR 0.58-3.0) and 64.3% had biliary atresia. Mean age at survey was 23.0 ± 4.4 years: 62% attended college, 68% lived with parents and 80% of those over 23 were employed. Patient health utilities were lower than norms (0.75 ± 0.12 vs. 0.82 ± 0.18, p < 0.01) and correlated with unemployment (p < 0.042), hospitalizations (p < 0.005) and lower education level (p < 0.016). Lower PedsQL™3.0 Transplant Module and PedsQL™ 4.0 Generic Core Scale scores correlated with unemployment (p = 0.006, p = 0.009) and hospitalizations (p = 0.006, p = 0.02). Pediatric transplant recipients who survive to adulthood have lower physical HRQOL, measurable transplant-related disability and lower health utility. Transplantation is life saving; however, physical and psychological sequelae continue to affect health status up to two decades later.

Resource use, costs, and utility estimates for patients with cystic fibrosis with mild impairment in lung function: analysis of data collected alongside a 48-week multicenter clinical trial

OBJECTIVES

Transport of ions to generate epithelial rehydration (TIGER)-1 was a randomized trial conducted to evaluate the safety and efficacy of denufosol versus placebo in patients with cystic fibrosis with mild impairment in lung function. The trial met its primary end point at 24 weeks, but a subsequent trial did not show a sustained effect of denufosol at 48 weeks. By using the 48-week data, we characterized resource use, direct medical costs, indirect costs, and utility estimates.

METHODS

Data on medications, outpatient and emergency visits, hospital admissions, tests, procedures, and home nursing were captured on study case report forms. Sources for unit costs included the Medicare Physician Fee Schedule, the Nationwide Inpatient Sample, and the Red Book. Health utilities were derived from the Health Utilities Index Mark 2/3. We used multivariable regression to evaluate the impact of baseline covariates on costs.

RESULTS

Characteristics of the 352 participants at enrollment included mean age of 14.6 years, history of Pseudomonas aeruginosa colonization in 45.2%, use of dornase alfa in 77.0%, and long-term use of inhaled antibiotics in 37.2%. Over 48 weeks, 22.4% of participants were hospitalized and, on average, participants missed 7.4 days of school or work. Mean total costs (excluding denufosol) were $39,673 (SD $26,842), of which 85% were attributable to medications. Female sex and P. aeruginosa colonization were independently associated with higher costs.

CONCLUSIONS

Prospective economic data collection alongside a clinical trial allows for robust estimates of cost of illness. The mean annual cost of care for patients with cystic fibrosis with mild impairment in lung function exceeds $43,000 and is driven by medication costs.

Preferences for type 2 diabetes health states among adolescents with or at risk of type 2 diabetes mellitus

OBJECTIVE

We evaluated how adolescents with or at risk of type 2 diabetes (T2DM) and their parent/guardians (parents) value health states associated with T2DM.

METHODS

We interviewed overweight/obese [Body Mass Index (BMI) ≥ 85th percentile], 12-18-yr old adolescents with T2DM, prediabetes, or insulin resistance (IR) and a parent. The standard gamble (SG) method elicited preferences (utilities) for seven hypothetical T2DM health states reported on a scale from 0 (dead) to 1 (perfect health). Adolescent's current health was evaluated with the SG and Health Utilities Index (HUI).

RESULTS

There were 70 adolescents and 69 parents. Adolescents were 67.1% female and 15.5 ± 2.2 yr old; 30% had T2DM, 30% prediabetes, and 40% IR. Almost half (48.6%) had a BMI > 99th percentile. Parents (83% mothers) were 45.1 ± 7.3 yr old and 75% had at least some college/technical school education. Adolescents and parents rated T2DM with no complications treated with diet as most desirable [median (IQR); adolescent 0.72 (0.54, 0.98); parent 1.0 (0.88, 1.0)] and end-stage renal disease as least desirable [adolescent 0.51 (0.31, 0.70); parent 0.80 (0.65, 0.94)]. However, adolescents' utilities were significantly lower (p ≤ 0.001) than parents for all health states assessed. Adolescents' assessments of their current health with the SG and HUI were not correlated.

CONCLUSIONS

Adolescents with or at risk of T2DM rated treatments and sequelae of diabetes as significantly worse than their parents. These adolescent utilities should be considered in the evaluation of treatment strategies for youth with T2DM. Family-based programs for T2DM must also be prepared to address conflicting preferences in order to promote shared decision-making.

Quality of life of adolescent kidney transplant recipients

OBJECTIVE

To elicit utility-based quality of life (QOL) of adolescent kidney transplant recipients.

STUDY DESIGN

We measured QOL in adolescent transplant recipients by using a visual analog scale (VAS), and 2 utility-based QOL measures, the Health Utilities Index (HUI) Mark 2/3 (HUI2/3), and the time trade-off. Participants aged 11-19 years old were recruited from 5 transplantation centers in Australia. Mean scores were compared by using paired t tests, and linear multiple regression was used to define predictors for time trade-off QOL weights.

RESULTS

Twenty-six adolescents participated in the study. On a scale with extremes of 0 (death) and 1 (full health), the participants had a mean (SD) time trade-off QOL weight of 0.99 ± 0.01 and HUI2/3 utility scores of 0.86 ± 0.16 and 0.85 ± 0.21, respectively. Time trade-off values were significantly higher than HUI Mark 2 values (P = .01) and HUI Mark 3 values (P = .02). From the HUI measure, decrements were observed in specific QOL domains, including vision, emotion (depression and anxiety), cognition, and pain.

CONCLUSION

Adolescent kidney transplant recipients had consistent and high values for their current QOL, which suggests that they perceive themselves to be close to full health. However, adequate emotional and cognitive support may improve their overall QOL.

Predictors of risk tolerance among oral surgery patients

PURPOSE

This study attempts to provide insight on how the treatment preference for a mandible fracture and treatment received and its consequences are related to the patient's risk tolerance, as measured by the Standard Gamble (SG).

PATIENTS AND METHODS

Data from a prospective cohort study of 203 subjects receiving treatment at the former King/Drew Medical Center in Los Angeles, CA, for either a mandible fracture (n = 98) or third molar removal (n = 105) were examined. Subjects were interviewed at 4 time points: on admission to the medical center and at 3 monthly follow-up visits. Risk tolerance for hypothetical treatment scenarios is measured by use of the SG, a health-value utility measure assessing the tradeoff between good outcomes and serious complications associated with treatment. Separate regression analyses with subsets of predictors (sociodemographic, psychosocial health, and clinical characteristics) were conducted and then synthesized by use of the significant predictors in separate analyses.

RESULTS

For fracture subjects, there was a noticeable rise in the SG reports from admission to the 1-month follow-up. Their greater risk tolerance was associated with being older, receiving surgery, having a lower post-traumatic stress disorder score, and having a swollen jaw or face. For third molar subjects, SG did not change substantively over the course of the study. Predictors of greater risk tolerance for third molar subjects included the jaw or face being swollen and having to use less pain medication.

CONCLUSIONS

Findings from this study show a preference for less invasive treatment, with the majority of both groups preferring wiring, and support the theory that treatment choices differ between subjects with different health states. Factors associated with risk tolerance include the patient's age, treatment received, psychosocial health state, experience with previous treatment, and value for oral health quality of life.

Changes in lung function in young cystic fibrosis patients between two courses of intravenous antibiotics against Pseudomonas aeruginosa

BACKGROUND AND AIMS

Repeated intravenous antibiotic therapy (IVAT) against chronic pulmonary infection with Pseudomonas aeruginosa is often necessary in cystic fibrosis patients (CF). The aim of this study was to monitor kinetics of degradation of pulmonary and nutritional status after IVAT in CF patients.

METHODS

Lung function, nutritional status and physical activity (PA) were measured for 21 CF patients (mean +/- SD age, 16 +/- 1.9 years; 9 boys) who were chronically colonized by P. aeruginosa. Each parameter was measured every 15 days during 3-6 months.

RESULTS

Nutritional status as well as PA did not change in the interval of 2 IVAT. In contrary, lung function worsened with a decrease of -14.6% of the FEV(1) (P < 0.05).

CONCLUSION

In CF, there is a progressive decrease in lung function without any evident deterioration of nutritional status and PA between two IVAT.

Why people refuse to make tradeoffs in person tradeoff elicitations: a matter of perspective?

OBJECTIVE

Person tradeoff (PTO) elicitations assess people's values for health states by asking them to compare the value of treatment programs. For example, people might be asked how many patients need to be cured of health condition X to equal the benefit of curing 100 people of condition Y. However, when faced with PTO elicitations, people frequently refuse to make quantifiable tradeoffs, exhibiting 2 kinds of refusals: 1) They say that 2 treatment programs have equal value, that curing 100 of X is just as good as curing 100 of Y, even if X is a less serious condition than Y, or 2) they say that the 2 programs are incomparable, that millions of people need to be cured of X to be as good as curing 100 of Y. The authors explore whether people would be more willing to make tradeoffs if the focus was changed from trading off groups of patients to choosing the best decision or evaluating treatment benefits.

DESIGN

. Two randomized trials used diverse samples (N=2400) via the Internet to test for the effect of perspective on refusal rates. The authors predicted that perspectives that removed people from decision-making roles would increase their willingness make tradeoffs.

RESULTS

Contrary to expectations, refusal rates increased when people were removed from decision-making roles. In fact, the more pressure put on people to make a decision, the less likely they were to refuse to make tradeoffs.

CONCLUSION

To reduce PTO refusals, it is best to adopt a decision-maker perspective.

Quality of life and congenital heart defects: comparing parent and professional values

OBJECTIVE

To compare preferences obtained from health professionals with those from parents for the longer-term health outcomes of children with congenital heart defects.

SETTING

Cardiology conference; hospital.

PARTICIPANTS

109 paediatric cardiology professionals (72% female, median age 38 years) and 106 parents of children with congenital heart defects (82% female, median age 37 years).

INTERVENTIONS

Eight health state descriptions, for cardiac and neurological disability resulting from congenital heart defects, were developed and presented with a self-administered anonymous questionnaire. Respondents were asked to rank health state descriptions from best to worst, score each health state using a visual analog scale and mark death on this scale.

RESULTS

Health professionals and parents agreed in the order of ranking health states from best to worst. Both groups assigned the lowest scores to health states with severe neurological disability. Scores did not differ significantly by age, sex or whether the respondent was in the health professional or parent group. Of all respondents, 8% (17) scored at least one health state description worse than death.

CONCLUSIONS

Parents and health professionals place similar values on the quality of life outcomes of children with congenital heart defects. Both are more averse to health states describing worse neurological than cardiac disability. Improving our understanding of the relative importance of different outcomes to children and families is an important basis for sharing decisions about clinical care. The views of young people with congenital heart defects should be an important focus for future enquiry into health outcomes.

What postoperative outcomes matter to pediatric patients?

Children are often excluded from making decisions related to their medical treatment, and parents' proxy reports are often used. This approach fails to consider that parents and children may differ in their perception of the child's health. In this study, we assessed children's decision-making processes related to postoperative pain management. Forty-five children who underwent an anterior cruciate ligament repair or Nuss procedure for pectus excavatum repair were studied. A standard gamble technique was used to assess children's perceptions of the utility of a hypothetical treatment that would provide them with perfect pain control, with respect to different rates of risk for vomiting during the postoperative period. The maximum risk of vomiting that the overall study population was willing to accept to decrease the pain level to zero was 32% +/- 24%. Girls were willing to take a significantly higher risk (41% +/- 24%) compared to boys (25% +/- 22%) (P = 0.02). Children who actually experienced vomiting before they were questioned were willing to take a higher risk (46% +/- 26%) compared to those who did not (23% +/- 17%) (P = 0.035). Children can express opinions about preferred postoperative outcomes and provide useful input about their care. Girls, more than boys, seem to perceive vomiting as less important than improved pain control in the postoperative period.

Health values of patients coinfected with HIV/hepatitis C: are two viruses worse than one?

OBJECTIVES

We sought to assess health values of patients coinfected with HIV/hepatitis C (HCV) and compare them with those of patients singly infected with HIV or HCV and to characterize and assess the relationship of clinical and nonhealth-related factors with health values.

SUBJECTS

We studied a total of 203 subjects infected with HIV, HCV, or both.

MEASURES

We assessed rating scale (RS), time tradeoff (TTO), and standard gamble (SG) values, and we explored associations of health values with the Mental Component Summary (MCS) and Physical Component Summary (PCS) of the SF-12; number of bothersome symptoms from the HIV Symptoms Index; spirituality, as assessed by the Functional Assessment of Chronic Illness Therapy, Spiritual Well-being scale; as well as with a number of demographic, clinical, and psychosocial characteristics.

RESULTS

Of the 203 subjects, 59 (29%) had HIV monoinfection, 69 (34%) had HCV monoinfection, and 75 (37%) were coinfected. The mean (SD) health values for the cohort were: RS = 0.69 (0.23), TTO= 0.88 (0.24), and SG = 0.78 (0.30). Infection type was related, albeit differently, to TTO values (mean values for patients with coinfection = 0.82; HIV = 0.91; and HCV = 0.91 [P < 0.05]) and SG values (coinfection = 0.77; HIV = 0.70; and HCV = 0.87; P < 0.05). In multivariable models, RS scores were significantly associated with sexual orientation, PCS scores, MCS scores, symptoms, and spirituality (adjusted R = 0.61); TTO with symptoms and spirituality (adjusted R = 0.23); and SG with infection type, PCS scores, and symptoms (adjusted R = 0.24).

CONCLUSIONS

Health values and their correlates varied by method of assessment. Health values appear to be driven more by symptoms, health status, and spirituality than by number of viral infections.

Gender differences in health-related quality of life of adolescents with cystic fibrosis

Background

Female patients with cystic fibrosis (CF) have consistently poorer survival rates than males across all ages. To determine if gender differences exist in health-related quality of life (HRQOL) of adolescent patients with CF, we performed a cross-section analysis of CF patients recruited from 2 medical centers in 2 cities during 1997–2001.

Methods

We used the 87-item child self-report form of the Child Health Questionnaire to measure 12 health domains. Data was also collected on age and forced expiratory volume in 1 second (FEV₁). We analyzed data from 98 subjects and performed univariate analyses and linear regression or ordinal logistic regression for multivariable analyses.

Results

The mean (SD) age was 14.6 (2.5) years; 50 (51.0%) were female; and mean FEV₁ was 71.6% (25.6%) of predicted. There were no statistically significant gender differences in age or FEV₁. In univariate analyses, females reported significantly poorer HRQOL in 5 of the 12 domains. In multivariable analyses controlling for FEV₁ and age, we found that female gender was associated with significantly lower global health (p < 0.05), mental health (p < 0.01), and general health perceptions (p < 0.05) scores.

Conclusion

Further research will need to focus on the causes of these differences in HRQOL and on potential interventions to improve HRQOL of adolescent patients with CF.

Generic health-related quality-of-life assessment in children and adolescents: methodological considerations

The health-related quality of life (HR-QOL) of children and adolescents is increasingly considered a relevant topic for research. Instruments to assess quality of life in children and adolescents of a generic as well as disease- or condition-specific nature are being developed and applied in epidemiological surveys, clinical studies, quality assurance and health economics. This paper attempts to give an overview on the state of the art of HR-QOL assessment in children as it relates to methodological and conceptual challenges. Instruments available in international or cross-cultural research to assess HR-QOL in generic terms were identified and described according to psychometric data provided and the width of application. In an initial literature search, several challenges in the assessment of child and adolescent HR-QOL were identified, ranging from conceptual and methodological to practical aspects. Seven specific major issues were considered: (i) What are the dimensions of HR-QOL relevant for children and adolescents, and do suitable instruments for their measurement exist? (ii) Can these dimensions be collected in a cross-culturally comparable way? (iii) What advantages and disadvantages do self-rated versus externally evaluated HR-QOL measurements of children and adolescents have? (iv) How can HR-QOL be assessed in an age-appropriate way? (v) What are the advantages and disadvantages of disease-specific and generic data collection? (vi) What advantages and disadvantages do profile and index instruments have? (vii) How can HR-QOL be connected with utility- preference values? In a second literature search we identified nine generic HR-QOL instruments and four utility health state classification systems that complied with the prespecified inclusion criteria. It was concluded that (i) HR-QOL instruments are available to assess the dimensions of the construct relevant to children and adolescents; (ii) provided that an instrument was constructed in an appropriate way, the dimensions of HR-QOL can be measured in an interculturally comparable manner; (iii) the HR-QOL of children and adolescents can and should be ascertained by self-rating; (iv) the measurement instruments used have to consider maturity and cognitive development; (v) only generic quality-of-life instruments allow for an assessment of HR-QOL in both healthy and chronically ill children and adolescents; (vi) the representation of HR-QOL achieved through a singular index value is connected to strict psychometric conditions: the index instrument has to be tailored to these psychometric conditions; (vii) how far utility measures are employable with children and adolescents has to be investigated in further studies. The problem aspects identified indicate the necessity for further research. Nevertheless, instruments for assessing the HR-QOL of children and adolescents can be identified that meet the requirements mentioned above.

Health of children with chronic arthritis: relationship of different measures and the quality of parent proxy reporting

OBJECTIVE

To examine the strength of the association between different measures of health-related quality of life (HRQOL), disability, pain, and well-being in children with chronic arthritis. To evaluate whether HRQOL scores vary as a function of disability status beyond chance. To assess the quality of the parent proxy report for HRQOL as compared with disability, pain, and well-being.

METHODS

Measures of HRQOL (visual analog scale [VAS] of health, Pediatric Quality of Life Inventory [PedsQL], Juvenile Arthritis Quality of Life Questionnaire (JAQQ), and modified standard gamble technique [SG]), disability (Childhood Health Assessment Questionnaire), VAS of pain, and VAS of well-being (VAS-well) were completed by the parents (n = 119) and patients > or =8 years (SG: > or =12 years).

RESULTS

HRQOL was highest when measured by the SG, whose utilities were no more than weakly correlated with any of the other outcomes. The values of all other HRQOL measures were at least moderately correlated with each other and with the VAS-well. Irrespective of the measure used, disability was associated with significantly decreased HRQOL. There was fair to good agreement and moderate consistency of the HRQOL ratings (SG: fair consistency) between patients and parents with marked differences between health domains.

CONCLUSION

HRQOL measured by the PedsQL, JAQQ, and VAS are moderately to highly correlated with each other in children with chronic arthritis. The children's HRQOL significantly decreases with increasing disability. Despite more pronounced differences for some health domains, parents are moderate to good proxy reporters of HRQOL, disability, and well-being of children with chronic arthritis.

The generation gap: differences between children and adults pertinent to economic evaluations of health interventions

Differences between children and adults have both technical and ethical implications for the design, interpretation and employment of economic analyses of health-related programmes. Even though policy makers increasingly turn to economic analyses to inform decisions about resource allocation, pertinent child-adult differences have received fragmented discussion in leading methodological references. Key areas warranting attention include: the ways in which a child's distinctive biology modifies the cost and effectiveness of healthcare interventions; challenges in assessing utilities for infants and young children given their limited but developing cognitive capacity; how a child's age, dependency and disability affect the selection of the appropriate time horizon and scope of the analysis; whether a child's non-wage earning productivity should be incorporated into analyses, and if so, what metric to use; what principles of equity policy makers should employ in using economic evaluations to choose between child- and adult-focused interventions; and whether special protective measures should be introduced to secure the rights and interests of children who cannot advocate for themselves.