The UKNHS Economic Evaluation Database - Economic issues in evaluations ofhealth technology

Objective: The U.K. NHS Economic Evaluation Database (EED) project is commi ssioned to identify papers on economic evaluations of health technologies a nd to disseminate their findings to NHS decision makers by means of structu red abstracts that are available through a public database and the Cochrane Library. This paper discusses current issues relating to the economic aspe cts of producing NHS EED abstracts. Methods: A review of NHS EED was undertaken between 1994 and 1999 to determ ine the methodologies adopted and issues that influence the usefulness of e conomic evaluations. Methods adopted to improve the quality of NHS EED abst racts are also reported. Results: Eighty-five percent of NHS EED abstracts are cost-effectiveness an alyses (CEAs), 9.3% are cost-utility analyses (CUAs), and only 1.4% are cos t-benefit analyses (CBAs). Of the total abstracts, 65.9% are based on singl e studies, 19.5% on reviews, 3.9% on estimates of effectiveness, and 10.7% on combinations of these sources. Models are utilized in 16.7% of CEAs, 60. 2% of CUAs, and 20% of CBAs. Analyses of CBA studies reveal a degree of mis use of well-established definitions. NHS EED internal control mechanisms ar e reported that provide a means of ensuring that abstracts are based on sou nd academic principles. Conclusions: Most economic evaluations are conducted by means of CEA, follo wed by CUA, while CBA accounts for an extreme minority of cases. Single stu dies form the principal source of effectiveness data, although models are w idely used, principally in CUA. The structure of NHS EED abstracts provides decision makers with the principal results and an interpretation of the re lative strengths and weaknesses of economic evaluations.