Abstract:
:Systematic reviews often provide recommendations for further research. When meta-analyses are inconclusive, such recommendations typically argue for further studies to be conducted. However, the nature and amount of future research should depend on the nature and amount of the existing research. We propose a method based on conditional power to make these recommendations more specific. Assuming a random-effects meta-analysis model, we evaluate the influence of the number of additional studies, of their information sizes and of the heterogeneity anticipated among them on the ability of an updated meta-analysis to detect a prespecified effect size. The conditional powers of possible design alternatives can be summarized in a simple graph which can also be the basis for decision making. We use three examples from the Cochrane Database of Systematic Reviews to demonstrate our strategy. We demonstrate that if heterogeneity is anticipated, it might not be possible for a single study to reach the desirable power no matter how large it is.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Roloff V,Higgins JP,Sutton AJdoi
10.1002/sim.5524subject
Has Abstractpub_date
2013-01-15 00:00:00pages
11-24issue
1eissn
0277-6715issn
1097-0258journal_volume
32pub_type
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