Sourcing and Using Appropriate Health State Utility Values in Economic Models in Health Care

Quality Appraisal in Systematic Literature Reviews of Studies Eliciting Health State Utility Values: Conceptual Considerations

BACKGROUND

The increasing number of studies that generate health state utility values (HSUVs) and the impact of HSUVs on cost-utility analyses make a robust tailored quality appraisal (QA) tool for systematic reviews of these studies necessary.

OBJECTIVE

This study aimed to address conceptual issues regarding QA in systematic reviews of studies eliciting HSUVs by establishing a consensus on the definitions, dimensions and scope of a QA tool specific to this context.

METHODS

A modified Delphi method was used in this study. An international multidisciplinary panel of seven experts was purposively assembled. The experts engaged in two anonymous online survey rounds. After each round, the experts received structured and controlled feedback on the previous phase. Controlled feedback allowed the experts to re-evaluate and adjust their positions based on collective insights. Following these surveys, a virtual face-to-face meeting was held to resolve outstanding issues. Consensus was defined a priori at all stages of the modified Delphi process.

RESULTS

The response rates to the first-round and second-round questionnaires and the virtual consensus meeting were 100%, 86% and 71%, respectively. The entire process culminated in a consensus on the definitions of scientific quality, QA, the three QA dimensions-reporting, relevance and  methodological quality-and the scope of a QA tool specific to studies that elicit HSUVs.

CONCLUSIONS

Achieving this consensus marks a pivotal step towards developing a QA tool specific to systematic reviews of studies eliciting HSUVs. Future research will build on this foundation, identify QA items, signalling questions and response options, and develop a QA tool specific to studies eliciting HSUVs.

Systematic methodological review of health state values in glaucoma cost-utility analyses

IMPORTANCE

Describing the characteristics and sources of health state utility values and reporting practice in the literature of cost-utility analyses facilitates an understanding of the level of the transparency, validity, and generalizability of cost-utility analyses. Improving the quality of reporting will support investigators in describing the incremental value of emerging glaucoma interventions.

OBJECTIVE

To describe the state of practice among published glaucoma cost-utility analysis studies, focusing on valuation of health and the quality of reporting.

EVIDENCE REVIEW

We searched several databases including Medline, CINHAL, Embase, Web of Science, Scopus, Biosis previews, the Health Economic Evaluations Database, and the NHS Economic Evaluation Database (NHS EED). We included full-text, English, published cost-utility analyses of glaucoma interventions with quality-adjusted life years (QALYs) as the primary outcome measure to calculate incremental cost-utility ratios. Excluded studies were non-English language, reviews, editorials, protocols, or other types of economic studies (cost-benefit, cost-minimization, cost-effectiveness). Study characteristics, operational definitions of glaucoma health states and health state utilities were extracted. The original source of the health utility was reviewed to determine the scale of measurement and the source of preference weighting. Items from the Systematic Review of Utilities for Cost-Effectiveness (SpRUCE checklist) were used to assess the reporting and quality of health utilities in glaucoma CUA.

FINDINGS

43 CUAs were included, with 11 unique sources of health utilities. A wide range of health utilities for the same Hodapp-Parrish-Anderson glaucoma health states were reported; ocular hypertension (0.84-0.95), mild (0.68-0.94), moderate (0.57-0.92), advanced (0.58-0.88), severe/blind (0.46-0.76), and bilateral blindness (0.26-0.5). Most studies reported the basis for using health utilities (34, 79%) and any assumptions or adjustments applied to the health utilities (22, 51%). Few studies reported a framework for assessing the relevance of health utilities to a decision context (8, 19%). Even fewer (3, 7%) applied a systematic search strategy to identify health utilities and used a structured assessment of quality for inclusion. Overall, reporting has not improved over time.

CONCLUSIONS AND RELEVANCE

This review describes that few CUAs describe important rationale for using health state utility values. Including additional details on the search, appraisal, selection, and inclusion process of health utility values improves transparency, generalizability and supports the assessment of the validity of study conclusions. Future investigations should aim to use health utilities on the same scale of measurement across health states and consider the source and relevance to the decision context/purpose of conducting that cost-utility study.

Quality appraisal for systematic literature reviews of health state utility values: a descriptive analysis

BACKGROUND

Health state utility values (HSUVs) are an essential input parameter to cost-utility analysis (CUA). Systematic literature reviews (SLRs) provide summarized information for selecting utility values from an increasing number of primary studies eliciting HSUVs. Quality appraisal (QA) of such SLRs is an important process towards the credibility of HSUVs estimates; yet, authors often overlook this crucial process. A scientifically developed and widely accepted QA tool for this purpose is lacking and warranted.

OBJECTIVES

To comprehensively describe the nature of QA in published SRLs of studies eliciting HSUVs and generate a list of commonly used items.

METHODS

A comprehensive literature search was conducted in PubMed and Embase from 01.01.2015 to 15.05.2021. SLRs of empirical studies eliciting HSUVs that were published in English were included. We extracted descriptive data, which included QA tools checklists or good practice recommendations used or cited, items used, and the methods of incorporating QA results into study findings. Descriptive statistics (frequencies of use and occurrences of items, acceptance and counterfactual acceptance rates) were computed and a comprehensive list of QA items was generated.

RESULTS

A total of 73 SLRs were included, comprising 93 items and 35 QA tools and good recommendation practices. The prevalence of QA was 55% (40/73). Recommendations by NICE and ISPOR guidelines appeared in 42% (16/40) of the SLRs that appraised quality. The most commonly used QA items in SLRs were response rates (27/40), statistical analysis (22/40), sample size (21/40) and loss of follow up (21/40). Yet, the most commonly featured items in QA tools and GPRs were statistical analysis (23/35), confounding or baseline equivalency (20/35), and blinding (14/35). Only 5% of the SLRS used QA to inform the data analysis, with acceptance rates of 100% (in two studies) 67%, 53% and 33%. The mean counterfactual acceptance rate was 55% (median 53% and IQR 56%).

CONCLUSIONS

There is a considerably low prevalence of QA in the SLRs of HSUVs. Also, there is a wide variation in the QA dimensions and items included in both SLRs and extracted tools. This underscores the need for a scientifically developed QA tool for multi-variable primary studies of HSUVs.

Towards Transparency in the Selection of Published Health Utility Inputs in Cost-Utility Analyses: The Health Utility Application Tool (HAT)

BACKGROUND

Evaluating the relevance of published health utilities to the context of a cost-utility analysis (CUA) remains an essential, yet often overlooked, task.

OBJECTIVE

The objective of this study was to provide guidance on this process through the development of the Health utility Application Tool (HAT).

METHODS

We conducted semi-structured telephone interviews with Canadian stakeholders from reimbursement bodies, academia, and the pharmaceutical industry to identify current practices and perspectives of the application of the health utility literature to CUAs. An online survey with international members of the general health economics and outcomes research community was also conducted to gather opinions on key concepts.

RESULTS

Based on the themes emerging from the interviews and online questionnaire, the HAT includes questions prompting investigators to consider the following constructs: similarity of the clinical condition in the health utility study and the CUA; similarity of health utility study participant demographics and the demographics of the CUA's target population; similarity of the health state descriptions in the health utility study and the CUA; and the method of assigning utility weights. Considerations of transparency prompted additional items, including: means by which the health utility study was identified; type of respondents; study design; and measure used to collect health utility estimates.

CONCLUSION

The HAT is intended to guide the evaluation of the applicability of published health utilities for a CUA, thus promoting transparency and accountability in the selection of model inputs.

Secondary progressive multiple sclerosis: a systematic review of costs and health state utilities

Objective: To identify evidence in the literature presenting the economic and humanistic (based on health state utility values [HSUVs]) burden of multiple sclerosis (MS) and report the incremental burden of secondary progressive MS (SPMS) compared with relapsing-remitting MS (RRMS).Methods: Electronic databases (Embase, MEDLINE, MEDLINE In-Process, Cochrane Library) and other relevant repositories were systematically searched from the date of inception until November 2019 for evidence on the economic burden of MS, or HSUVs in patients with MS. Data were extracted from studies investigating cost data or HSUVs for patients with SPMS compared with RRMS.Results: In total, 25 studies were identified that reported data on the economic and HSUV burden of SPMS versus RRMS: 18 studies reported cost data and nine presented HSUVs. Overall, costs associated with SPMS were consistently higher than those for RRMS. Major cost drivers appeared to shift following transition from RRMS to SPMS, with higher direct medical costs associated with RRMS than with SPMS, while the opposite was true for direct non-medical costs and indirect costs. In all studies presenting HSUVs specifically in patients with SPMS, the disease burden was greater (indicated by lower HSUV scores or a negative regression coefficient vs RRMS) for patients with SPMS than for those with RRMS. Fatigue and psychological stress (including depression) were identified as key drivers of this reduced health-related quality of life (HRQoL).Conclusions: Our findings indicate that SPMS is associated with higher costs and more substantial HRQoL decrements than RRMS. These results highlight the substantial unmet need for effective treatments that can slow disease progression in patients with SPMS, which, in turn, would reduce the rate of HRQoL deterioration and increasing healthcare costs.