Bias in published cost effectiveness studies: systematic review

Abstract

Objective To investigate if published studies tend to report favourable cost effectiveness ratios (below $20 000, $50 000, and $100 000 per quality adjusted life year (QALY) gained) and evaluate study characteristics associated with this phenomenon. Design Systematic review. Studies reviewed 494 English language studies measuring health effects in QALYs published up to December 2001 identified using Medline, HealthSTAR, CancerLit, Current Content, and EconLit databases. Main outcome measures Incremental cost effectiveness ratios measured in dollars set to the year of publication. Results Approximately half the reported incremental cost effectiveness ratios (712 of 1433) were below $20 000/QALY. Studies funded by industry were more likely to report cost effectiveness ratios below $20 000/QALY (adjusted odds ratio 2.1, 95% confidence interval 1.3 to 3.3), $50 000/QALY (3.2, 1.8 to 5.7), and $100 000/QALY (3.3, 1.6 to 6.8). Studies of higher methodological quality (adjusted odds ratio 0.58, 0.37 to 0.91) and those conducted in Europe (0.59, 0.33 to 1.1) and the United States (0.44, 0.26 to 0.76) rather than elsewhere were less likely to report ratios below $20 000/QALY. Conclusion Most published analyses report favourable incremental cost effectiveness ratios. Studies funded by industry were more likely to report ratios below the three thresholds. Studies of higher methodological quality and those conducted in Europe and the US rather than elsewhere were less likely to report ratios below $20 000/QALY.

Publication Patterns of Cancer Cost-Effectiveness Studies Presented at Major Conferences

“…It is also possible that the use of a societal perspective serves as a surrogate for higher-quality cost-utility analyses and therefore provided a more accurate estimation of the true icers. That explanation is also supported by the findings of Bell et al 12 suggesting that studies of higher methodologic quality were less likely to report icers below US$20,000 per qaly.…”

“…That result contrasts with the findings of Bell et al 12 , which suggested a trend of publication for favourable icers. The lack of evidence for publication bias has several potential explanations.…”

Updated Recommendations for Cost-effectiveness Studies

“…2 As a means to address this and other potential biases, we agree with the authors' recommendations to require a true societal health care perspective and include an impact inventory.…”

“…Their main recommendation for the inclusion of findings based on a societal perspective alongside the conventional health sector perspective will enable these types of studies to reflect the wider social benefits of improving health, particularly of interventions that primarily target health systems and populations rather than individuals. 2 In operationalizing a societal perspective, Sanders and colleagues 1 recommended the reporting of an impact inventory, which is an extensive list of outcomes attributed to the intervention including nonhealth as well as health indicators. Such lists are generally produced as part of a costconsequence analysis and are not new.…”

Who Should Conduct Modeling and Cost-Effectiveness Analysis?

“…Each regulatory Dear Dr Mäkelä, In our article "Romiplostim and eltrombopag for immune thrombocytopenia: methods for indirect comparison" published in the Journal (1), we presented an indirect comparison of the effectiveness of eltrombopag and romiplostim in raising platelet counts in patients with immune thrombocytopenia (ITP). Indirect comparison analyses are recommended by the National Institute for Health and Care Excellence (NICE) in cases where randomized head-to-head studies do not exist, and were used by NICE in their guidance for the eltrombopag Single Technology Appraisal submission (2).…”