Economic evaluation of diagnostic tests. A review of published studies

The purpose of this review was to examine whether studies from the medical literature focusing on efficiency of diagnostic facilities reported economic evaluation methods appropriately, following guidelines for conducting and reporting economic evaluations.

A Medline search was conducted, and studies that concerned a diagnostic technology and fulfilled the Drummond criteria were selected for methodological review. The reliability of selection and methodological review based on the abstracts was determined by scoring a random sample of both abstracts and full articles. Interrater reliability was determined by scoring a random sample of abstracts by both authors. Kappa values were calculated. Nine methodological aspects were reviewed: study design, the type of economic evaluation, the comparison made, the study's perspective, the cost-effectiveness ratio used, the definition of cost-effective, the types of costs analyzed, the cost calculation method, and the use of sensitivity analysis.

Two hundred fifty studies published between 1992 and 1997 were found regarding efficiency of diagnostic facilities; 134 studies fulfilled the Drummond criteria and were selected for methodological review. Kappa values showed reliability of selection and methodological review and interrater reliability. The existing literature on the economic evaluation of diagnostic facilities does not adhere well to guidelines for economic evaluation. In 95%, no perspective was mentioned, in 50% of the cases no ratio was given, in 82% the cost calculation method was not mentioned, and in 66% no sensitivity analysis was reported.

Our review suggests that to improve the quality of reporting economic evaluations, editorial boards could issue and enforce guidelines for standard reporting of such studies.