Research

A major objective of economic analyses is the measurement of value. Two major streams of activity can be distinguished in this field: the first falls into the realm of the conventional evaluation model, i.e., the “logic of cost effectiveness”, while the second addresses approaches to overcome the limitations of the current standard paradigm.

Multi-attribute utility (MAU) theory-based instruments to measure health-related quality of life (HRQoL)

Contemporary methods to measure health-related quality of life (HRQoL) for economic evaluation are grounded in multi-attribute utility theory. In the Multi-Instrument Comparison (MIC) study, all relevant instruments were systematically compared, revealing that while these instruments measure related constructs, they differ substantially in their sensitivity and content, with far-reaching implications for the valuation and thus economic comparison of different health care services. Analyses of the German branch of the MIC study were conducted (led by Michael Schlander as PI), and similar results were found as reported for Australia, Canada, Norway, and the United States. Findings were presented to and discussed with experts from international HTA agencies, including the German IQWiG.

Further analyses of MIC data showed how six different multi-attribute utility instruments (MAUIs)—EQ-5D, SF-6D, HUI-3, 15D, AQoL-4D, and AQoL-8D—vary in their sensitivity to the dimensions of the SF-36 HRQoL questionnaire. Using data from 8,022 participants across six countries, ordinary least squares regression was applied to assess relationships between SF-36 dimensions (such as physical functioning, mental health, and bodily pain) and utility scores from each MAUI. Results revealed that AQoL-8D is most sensitive to mental health, EQ5D to bodily pain, and 15D to physical functioning. This underscores the critical importance of selecting the appropriate MAUI based on the specific health domains of interest, as different instruments exhibit varied responsiveness to HRQoL changes.

Validity of health state utility values used for cost effectiveness analyses

Health state utility values (HSUVs) represent the weights individuals assign to medical interventions or medical technologies, serving as a critical input in cost effectiveness analysis (CEA) to adjust disease state durations and quality of life, ultimately contributing to quality-adjusted life years (QALYs). Despite their importance, there is no widely accepted quality assurance /QA) tool for interpreting and systematically reviewing HSUV studies.

A comprehensive review of QA practices in 73 SRLs of HSUVs published from January 2015 to April 2021 was conducted, highlighting the need for consensus on definitions and dimensions essential for a robust QA framework. An international, multidisciplinary expert panel of seven purposively selected members was established, employing a modified Delphi method with two anonymous online survey rounds followed by a virtual face-to-face meeting. The process achieved consensus on the definitions of scientific quality, QA, three QA dimensions (reporting, relevance, methodological quality), and the scope of a QA tool for systematic reviews of HSUV studies. Future research will focus on identifying QA items, signaling questions, and response options to finalize the tool, aiming to standardize and improve the evaluation of HSUV studies for more rigorous cost-effectiveness analysis in healthcare.

Selected Publications

1. Muchadeyi, M.T., Hernandez-Villafuerte, K., Schlander, M.: Quality appraisal for systematic literature reviews of health state utility values: a descriptive analysis. BMC Medical Research Methodology. 2022; 22(1): 303
2. Muchadeyi, M.T., ..., Schlander, M.: Quality Appraisal in Systematic Literature Reviews of Studies Eliciting Health State Utility Values: Conceptual Considerations.
   PharmacoEconomics. 2024; 42(7): 767-782
   
   

Social preferences and their measurement

In the European social preferences measurement (ESPM) project, a comprehensive review of the literature on social preferences with regard to the allocation of health care resources indicated empirical support for a number of characteristics or "attributes" (beyond clinical effectiveness) of interventions. In particular, these include: 1) giving priority to the worst-off patients (in terms of severity, related to the ex ante health state); 2) prioritizing urgent interventions (urgency, because of the risk of major irreversible consequences without intervention, which may be conceptualized as a component of “effectiveness”); 3) not discriminating against persons in "double-jeopardy" (or, more generally, persons with comorbid conditions); 4) prioritizing health care for younger over older patients (age or the "fair innings" argument); and wishing to share resources with patients even if their treatment costs are high, in order not to disenfranchise them from a fair chance of access to effective care.

A research program was initiated to investigate how citizens value selected characteristics (or "attributes") of health care interventions, and how they weigh them against each other; to compare the valuation results obtained in the project with those based on the conventional logic of cost effectiveness. Concerning orphan indications (or “rarity”, an attribute of primary interest), the studies indicated consistently that citizens are prepared to accept (sometimes much) higher cost per patient in rare and ultra-rare conditions.

In terms of outlook, the ESPM project was affected similarly as the Value of a Statistical Life (Year) [VSL(Y)] studies, and full publication of the main study is still outstanding. The critical follow-up survey to investigate the sensitivity of citizens’ WTP on size had to be put on hold. Currently, the working group is also re-initiating the “sensitivity-to-size” study.

In addition, further information on the Value of a Statistical Life (VSL) and the Value of a Statistical Life Year (VSLY) will be provided here soon.

Selected Publications

1. Richardson, J., Schlander, M.: Health Technology Assessment (HTA) and economic evaluation: Efficiency or fairness first. Journal of Market Access & Health Policy. 2019; 7(1): 1557981
2. Moro, D., Schlander, et al.: Evaluating discrete choice experiment willingness to pay [DCE-WTP] analysis, and relative social willingness to pay [RS-WTP] analysis in a health technology assessment of a treatment for an ultra-rare childhood disease [CLN2]. Expert Review or Pharmacoeconomics & Outcomes Research. 2022; 22(4): 581-598
3. Caro, J.J, ..., Schlander, M.: Determining value in Health Technology Assessment: Stay the course or tack away? PharmacoEconomics. 2019; 37(3): 293-299
4. Brougham, M., Schlander, M., et al.: Use of the incremental cost effectiveness ratio for decision-making policies - what's the problem? A perspective paper. Expert Review of Pharmacoeconomics & Outcomes Research. 2022; 22(6): 913-918