Caro et al. (2010)
aim to clarify a proposed method for technology appraisal in the German context, in which the 'efficiency frontier approach' to economic evaluation is central. This approach significantly deviates from conventional economic evaluations. An important reason for this appears to be the supposedly necessary avoidance of comparisons across diseases. However, the proposed methodology does not offer any real added value over conventional methodology. Not only because comparisons between diseases are as avoidable and possible under the efficiency frontier approach as under the conventional approach, but also because the efficiency frontier approach is difficult to operationalise and runs the risk of guiding policymakers to inferior decisions. In this brief comment, we highlight some of these issues.
2. RESTRICTIONS
Caro et al. emphasise that the German approach was developed under important restrictions, although their exact nature and origins remain rather unclear. The German law stipulates that IQWiG should adopt international standards as established within health economics. However, the common framework of judging cost per QALY ratios against some threshold (range) to determine whether interventions offer value for money was not adopted, as this would require 'judgments about the societal value of treating one disease versus another'. Caro et al. indicate that no universally accepted method to do so could be identified, including the QALY approach in combination with some relevant (range for the) threshold. Seemingly, there were no principle or legal arguments against this framework or comparisons between diseases; there was only a lack of a 'universally accepted' method.
As a consequence, 'IQWiG insisted' on a method that does not compare across diseases. Why this should be done by adopting a different approach remains unclear, as avoiding (direct) comparisons across diseases is quite possible (and even common) under conventional methodology as well. Paradoxically, therefore, the principle of adhering to international standards resulted in proposing a methodology that clearly deviates from international standards. Although judging cost-utility ratios against some relevant threshold certainly is not without problems, challenges, or debate, there appears to be a broad international agreement on the principles of the approach (e.g. Gold et al., 1996;Drummond and Rutten, 2008). The fact that IQWiG prefers to leave the final choice or the 'application of citizen values y to decision making bodies designated by law' is not unique either. Decisions are