Читать книгу Individual Participant Data Meta-Analysis - Группа авторов - Страница 25

Before deciding whether to collect IPD for meta‐analysis, an important step is to assess the completeness and uniformity of the available aggregate data, either based on a pre‐existing systematic review that addresses a similar research question, or by conducting a scoping or systematic review of existing trials of interest. If outcomes and participant‐level covariates have been collected in the eligible trials, but are not (adequately) described in the associated trial reports (such as side effects of treatment, multiple time‐points or continuous values of prognostic factors), this can be rectified by the collection and analysis of IPD. Even if all the outcomes, participant‐level covariates and, if relevant, interactions required for the analyses have been reported, if they are not defined consistently across trials it can be difficult to include or combine their results in aggregate data meta‐analysis in a meaningful way. At best, this could lead to findings that are difficult to interpret, and at worst, that are unreliable. If this is a cause for concern, IPD might be sought to allow standardisation of the variables in readiness for analysis (Section 4.5).