Quality of cost effectiveness studies in systematic reviews is problematic

EDITOR—Witten et al reviewed the cost effectiveness of telemedicine.1 In their response on bmj.com they confuse the evaluation of quality with levels of evidence and study design.2 Quality should not be judged on levels (strength) of evidence or whether health consequences were measured but on how well these were undertaken and reported.3

Additionally, studies were rated on the “presence of a clear hypothesis.” Although essential for assessing efficacy, this is less important for economic evaluations. Hypotheses require statistical testing to acceptance or rejection of the null hypothesis; economic evaluations typically use point estimates and, without variance, cannot be subjected to statistical testing. Hence, sensitivity analyses are required for testing the robustness of results. A clear statement of aims is required, and as noted by Witten et al, most economic evaluations do clearly state the aims.

Economic evaluations of telemedicine often concentrate on costs and cost minimisation, assuming health outcomes are at …