The study examples were drawn from two systematic reviews [1 (link),17 (link)]. [17 (link)] reported a meta-analysis on drugs for patients with Type-2 diabetes and [1 (link)] reported a meta-analysis on lowering intraocular pressure for patients with open angle glaucoma or ocular hypertension.
In order to compare the results obtained from our methods with that from [17 (link)], we first attempted to collect all the original information on sampling distributions from each of the clinical trials papers used in [17 (link)]. After going through these papers, we found that we could not get the sampling distributions with full information from every single paper, as some of these papers did not provide the SEM values. We then applied our two methods to merge these (including partial) distributions and compared the merged result with that obtained in [17 (link)]. In contrast to [17 (link)], in [1 (link)] every sampling distribution used has full statistical information. To test the adequacy of our methods for dealing with missing information, we randomly selected a trial from [1 (link)] and deleted its SEM value. We then applied our two methods to recover this missing SEM value before merging this trial with the rest. Finally, we compared our results with that from [1 (link)].
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