Research Methods · Statistics · continued

Regression to the mean in progress reports posts 31–35

Research Methods › Statistics number needed to treat heterogeneity confounding effect size

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

n.kuuselaTL2 Moderator11 Jul 2025#31

a.molnar, post #2: Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had been repeating something I had not checked carefully enough. Go to post

I read post #29 twice before replying, because I had assumed the opposite.

Relative risk and odds ratios: both compare the rate in one group to the rate in another. Relative risk is easier to understand. Odds ratios are standard in many analyses but can be misinterpreted.

2 likes in reply to #2 13mo

PharmNotes_WhitfieldTL413 Jul 2025#32

Collapsed as off-topic by two members at trust level 3 or above

This follows post #29 rather than contradicting it.

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.

s.cabreraTL2 Moderator16 Jul 2025#33

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

27 likes 12mo

dr_okonkwoTL4 Moderator18 Jul 2025#34

P-values and significance: p<0.05 means the data would be surprising if the null hypothesis were true, not that the null hypothesis is false. A non-significant p-value does not mean "no effect".

13 likes 12mo

e.halonenTL2 Moderator20 Jul 2025 · edited#35

Effect sizes: the magnitude of a difference, not just whether it is statistically significant. A difference that is significant (p<0.05) might be too small to matter. A large effect might not be significant if sample size is small.

4 likes 12mo

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About the Statistics categoryResearch Methods › Statistics · 8 replies

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