Cost-effectiveness analysis of health technologies when evidence is scarce

Abstract: Given the increasing pressures on health care budgets, economic evaluation is used in many countries to assist decision-making regarding the optimal use of competing health care technologies. Although the standard methods of estimating cost-effectiveness underpinning these decisions have gained widespread acceptance, concerns have been raised that many technologies would not be considered for funding, due to scarcity of evidence. However, as long as the amount and quality of evidence used for the analysis are properly characterized, scarce evidence per se should not be seen as a hindrance to perform cost-effectiveness analyses. Characterizing uncertainty appropriately, though, may pose a challenge even when there is a large body of evidence available, and even more so when evidence is scarce. The aims of this thesis are to apply a methodological framework of cost-effectiveness analysis and explore methods for characterising uncertainty when evidence is scarce. Three case studies associated with limited evidence provide economic evaluations on current decision problems, investigate the feasibility of using the framework, and explore methods for characterizing uncertainty when evidence is scarce.The results of the case studies showed that, given current information, providing transfemoral amputees with C-Leg and Airsonett Airshower to patients with perennial allergic asthma could be considered cost-effective whereas screening for hyperthrophic cardiomyopathy among young athletes is unlikely to be cost-effective. In the cases of C-Leg and Airsonett Airshower conducting further research is likely to be cost-effective. The case studies indicate that it is feasible to apply methods of cost-effectiveness in health care for technologies not commonly evaluated due to lack of evidence. The analysis showed that failing to account for individual experts’ might have a substantial effect on the interpretation of the results of cost-effectiveness analysis. Formal expert elicitation is a promising method of characterizing uncertainty when evidence is missing, and thus enable cost-effectiveness and value of further research to be appropriately estimated in such situations.In conclusion, this thesis shows that scarcity of evidence should not preclude the use of cost-effectiveness analysis. On the contrary, in such cases it is probably more important than ever to use a framework that enable us to define key parameters for a decision problem and identify available evidence in order to determine cost-effectiveness given current information and provide guidance on further data collection.