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Research Methods › Statistics effect size number needed to treat heterogeneity Pinned Wiki

This is a generated summary. It shows the 5 most-liked posts from a topic of 9, 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.

b.vestergaardTL2 Moderator22 Oct 2025#3

As a member rather than staff: the most useful thing I did when I started reading this category was to work through the tag pages rather than the topic list. The topic list shows you what is recent. The tags show you what is settled.

10 likes 9mo

CSagredoTL3Regular2 Nov 2025#4

Suggestion for the wiki post above: it would be worth linking the two or three most-referenced topics in this category directly, since new members reliably ask for exactly those. Happy to make the edit myself if nobody objects, with a revision note.

23 likes 9mo

a.vestergaardTL2 Moderator12 Nov 2025#5

s.leclerc, post #1: Effect sizes, intervals, multiplicity, and the difference between absent and undetected. This post is a community wiki: any member at trust level 3 or above can edit it, and every edit is recorded with its author and a note. If the scope described here has drifted from what actually gets posted, edit it rather than starting a topic… Go to post

Number needed to treat: how many people need to be treated to prevent one bad outcome or achieve one good outcome. More intuitive than relative risk reduction.

32 likes in reply to #1 8mo

glossary_checkTL2Member9 Dec 2025#8

l.krastev, post #7: P-values and significance: p Go to post

Absence of evidence and evidence of absence: if a study is small and finds no effect, that is absence of evidence, not evidence of absence. A larger study might find an effect that a small study missed.

16 likes in reply to #7 8mo

y.rahimiTL2 Moderator17 Dec 2025#9

post #8 is right about the mechanism and I think understates the practical bit.

For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.

24 likes in reply to #1 7mo

Read the full topic (9 posts)

Suggested topics

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Sample size intuition for a personal experiment — does this still hold? Research Methods › Statistics effect size heterogeneity number needed to treat Solved Sample size intuition for a personal experiment — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. Comparing STEP 1 ( N Engl J Med , 2021) with…	+33	38	26k	23d
Second pass at: Multiplicity when you track fifteen variables Research Methods › Statistics number needed to treat confounding effect size worked example Posting this under the heading it deserves: Second pass at: Multiplicity when you track fifteen variables Everything below is what sits behind that. I have seen SCALE ( N Engl J Med , 2015) cited in support…		2	12k	18mo
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