Contents
How does a meta-analysis of a cross-over trial work?
E-mail: [email protected] Background Meta-analysis of randomized controlled trials (RCTs) is usually based on trials where patients are randomized individually into two different, parallel, treatment groups. This paper concentrates on RCTs of a different design—two-period, two-treatment cross-over trials.
Why do crossover trials need to be reported?
The high proportion of poorly reported analyses and results has the potential to affect whether crossover data should or can be included in a meta-analysis. There is pressing need for reporting guidelines for crossover trials.
Can a parallel design be included in a meta-analysis?
For a large proportion of the trials, the authors tabulated the results as if they arose from a parallel design. Precision estimates properly accounting for the paired nature of the design were often unavailable from the study reports; consequently, to include trial findings in a meta-analysis would require further manipulation and assumptions.
Which is the best definition of a meta-analysis?
Meta-analysis is a statistical approach to the synthesis of quantitative data. It has been particularly used in the context of systematic reviews of randomized controlled trials (RCTs). The design of these RCTs is usually based on patients being randomized individually into two different, parallel, treatment groups.
What are the risks of cross over design?
A particular concern with the cross-over design is the risk of a carryover effect. Carryover occurs when the treatment given in the first period has an effect that carries over into the second period.
Which is a challenge for a meta analyst?
A challenge for meta-analysts is to find ways to incorporate RCTs of different designs into the synthesis, and to establish whether this is appropriate. This paper concentrates on cross-over trials, and considers issues of data synthesis in principle and in practice.