Determining Value in Health Technology Assessment: Stay the Course or Tack Away?

Abstract

The economic evaluation of new health technologies to assess whether the value of the expected health benefits warrants the proposed additional costs has become an essential step in making novel interventions available to patients. This assessment of value is problematic because there exists no natural means to measure it. One approach is to assume that society wishes to maximize aggregate health, measured in terms of quality-adjusted life-years (QALYs). Commonly, a single 'cost-effectiveness' threshold is used to gauge whether the intervention is sufficiently efficient in doing so. This approach has come under fire for failing to account for societal values that favor treating more severe illness and ensuring equal access to resources, regardless of pre-existing conditions or capacity to benefit. Alternatives involving expansion of the measure of benefit or adjusting the threshold have been proposed and some have advocated tacking away from the cost per QALY entirely to implement therapeutic area-specific efficiency frontiers, multicriteria decision analysis or other approaches that keep the dimensions of benefit distinct and value them separately. In this paper, each of these alternative courses is considered, based on the experiences of the authors, with a view to clarifying their implications.

Fig. 1

Empirical estimates of cost effectiveness relative to total cost, both axes on a logarithmic scale. The number beside each label is the total cost effectiveness, in thousands. Note, three categories—Social Care, Trauma, and Other—plotted on the horizontal axis have unknown cost effectiveness and only total cost. GBP Great British Pound, GI gastrointestinal, GU genitourinary, ID infectious disease, MSK musculoskeletal, UNK unknown, QALY quality-adjusted life-year

Fig. 2

Proposed relative value gradients according to quality-of-life improvement and initial severity (data taken from Nord [48])