Cost estimation in health economic evaluations in Germany: a systematic review

Abstract

The objectives of this study are (1) to systematically review the methods used in developing cost estimates in the recent German health economic literature and (2) to examine the methodological approaches in terms of analytical framework, cost components, resource-use and cost data sources in light of the national Institute for Quality and Efficiency in Healthcare guidelines. The MEDLINE database was searched for studies published between 1 January 2006 and 31 December 2008 estimating direct and/or indirect costs of healthcare interventions in Germany. Detailed information on the perspective of the analysis, time horizon for the cost estimation, resource-use categories analysed, costing approach, valuation of resource use, resource-use and unit cost/price data sources were systematically collected. The literature search returned citations to 122 articles, of which 47 fully met the inclusion/exclusion criteria. Nearly half of the selected articles (23) adopted the societal perspective. In nearly three-quarters of the studies (35) the time horizon of the base case analysis was no longer than 1 year. Among the most common unit cost sources of healthcare services were reimbursement fees for outpatient and hospital services. The variability in the studies reviewed was very high, making any categorisation and synthesis difficult. Nevertheless, some common features clearly emerged. Firstly, most cost estimates focus on direct medical costs only. Secondly, a comprehensive list or at least an exhaustive discussion of the relevant resource use is usually missing. Finally, the time horizon is often too short to capture all relevant cost drivers and the assessment of the medical resource use not always consistent with the perspective of the analysis.