Topic summary

What pooling buys you and what it destroys

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

This is a generated summary. It shows the 9 most-liked posts from a topic of 84, 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.

m.dalgaardTL3Regular3 Aug 2025#1

The question in the title: What pooling buys you and what it destroys I will give what I have already checked below so nobody repeats it.

The question about pooling buys that I actually want answered is the second one below. The first is context and I have kept it short.

Both are stated with units, and I have said what I already checked so that nobody repeats it.

24 likes 12mo

n.abernathyTL3Analytical chemist Solution15 Aug 2025#5

m.dalgaard, post #1: The question in the title: What pooling buys you and what it destroys I will give what I have already checked below so nobody repeats it. The question about pooling buys that I actually want answered is the second one below. The first is context and I have kept it short. Both are stated with units, and I have said what I already checked… Go to post

Where I part company with post #4, and it is a narrow parting.

Double extraction with disagreement resolution is standard and is worth checking for, because single extraction errors are common and non-random.

Worth checking against a second source before it gets quoted onward.

18 likes in reply to #1 11mo

b.dumitruTL23 Sep 2025#15

For anyone finding this later: the short answer on pooling buys is that it depends on one thing, and the rest of the thread is people identifying which thing.

29 likes 11mo

j.vandermolenTL3Regular20 Sep 2025#25

Answering the question post #23 raises rather than the one it answers.

Double extraction with disagreement resolution is standard and is worth checking for, because single extraction errors are common and non-random.

23 likes 10mo

batchlogTL3Regular7 Oct 2025#37

s.cabrera, post #8: The question underneath pooling buys is usually "how would I tell?" rather than "what is true?", and that one has a method attached to it. Write down what you would expect to see under each hypothesis before you collect anything. If they predict the same observation, collecting it will not help. Go to post

Building on post #34 rather than restating it.

Where the included trials share a sponsor and a protocol template, their errors correlate and pooling does not average them out.

If anyone has run this properly I would rather read that than my own guess.

26 likes in reply to #8 10mo

a.iyerTL218 Oct 2025#45

Post #41 and I disagree about the size of the effect, not about the direction.

Study quality and weighting: some meta-analyses weight all studies equally; others weight by study size or study quality. The choice affects the result and should be stated and justified.

I looked this up rather than remembered it, which is the right order.

30 likes 9mo

n.lehtinenTL219 Nov 2025#70

Confirming post #67 from a second method, which matters more than confirming it from a second person.

I disagree with the framing of pooling buys above, and I think it is a substantive disagreement rather than a terminological one. Setting out why, so it can be checked.

The reasoning depends on an assumption that is doing a lot of work and is never stated. If the assumption holds, the conclusion follows. I do not think it holds generally.

24 likes 8mo

batchlogTL3Regular27 Nov 2025#77

Taking post #74 at face value and following it one step further.

Double extraction with disagreement resolution is standard and is worth checking for, because single extraction errors are common and non-random.

Second-hand, so weight it accordingly.

25 likes 8mo

aliquot_lineTL3Regular3 Dec 2025#82

Adding a note of thanks rather than an opinion. I did not know most of that.

26 likes 8mo

Read the full topic (84 posts)

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