Topic summary

Second pass at: A pooled estimate that changed when one trial was added

Evidence › Meta-analyses effect size risk of bias publication bias meta-analysis Wiki

This is a generated summary. It shows the 5 most-liked posts from a topic of 31, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

f.laurentTL25 May 2026#1

Community wiki post. Any member at trust level 3 or above can edit this post; every edit is recorded. Last edited by n.rowntree on 9 Jun 2026.

9 Jun 2026 — n.rowntree: Corrected an arithmetic slip in the second example.

Editors: n.rowntree, bench_notes, buffer_sheet

On the subject in the title: Second pass at: A pooled estimate that changed when one trial was added Working notes rather than a conclusion.

Two things I would like separated before anyone answers on pooled estimate, because they get bundled and then argued about as one thing.

The first is descriptive: what has actually been observed, by whom, and how. The second is causal: why. I am asking about the first only.

39 likes 3mo

r.mensahTL214 May 2026#5

Picking up post #2: that is the part I would want checked first.

A meta-analysis of four small trials is not stronger evidence than one adequately powered trial, whatever the summary statistic looks like.

29 likes 2mo

j.ivaturiTL228 May 2026#15

I read the earlier replies on pooled estimate twice before writing this, because I had assumed the opposite and wanted to be sure I was disagreeing with what was said rather than what I expected.

29 likes 2mo

j.vogelTL24 Jun 2026#21

Post #20 answers the question as asked. The question underneath it is different.

A tighter confidence interval around a meaningless centre is worse than a wide interval around a meaningful one. Precision is not the objective.

28 likes 2mo

o.abrahamsenTL3Regular14 Jun 2026#30

Source for the pooled estimate figure, since it was asked for. It is in the discussion rather than the abstract, which is why the version circulating is stronger than the paper is.

Reading the surrounding paragraph is worth the two minutes. The authors are more careful than their summarisers.

29 likes 1mo

Read the full topic (31 posts)

This topic was referenced in

Prediction intervals and why they are more honest than confidence intervalsEvidence › Meta-analyses · 25 replies
[2026 update] Heterogeneity as information rather than as a nuisanceEvidence › Meta-analyses · 4 replies
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