Abstract:
:We examine different methods to pool binary outcomes used both in parallel and cross-over trials. Odds ratio (OR) estimators obtained from joint conditional probabilities in cross-over trials, such as the Mantel-Haenszel and Peto methods, are compared to an OR estimator using marginal results of cross-over trials. When there is correlation between the outcomes in the two cross-over periods, joint conditional ORs differ from marginal ORs and cannot be combined with OR estimates from parallel trials. The marginal OR estimate is independent of the between-period correlation and it includes a correction for cross-over correlation in the variance estimate. As its computation is similar in cross-over and parallel trials, it is the method of choice to pool results from parallel and cross-over trials in a combined design meta-analysis.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Curtin F,Elbourne D,Altman DGdoi
10.1002/sim.1206subject
Has Abstractpub_date
2002-08-15 00:00:00pages
2145-59issue
15eissn
0277-6715issn
1097-0258journal_volume
21pub_type
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