Research Methods · Statistics

What a confidence interval means, from scratch

Research Methods › Statistics number needed to treat confounding worked example heterogeneity

microgramsTL2Regular26 Apr 2026#1

What a confidence interval means, from scratch — that is the question, and I have not found it answered plainly anywhere I have looked.

Asking about confidence interval directly, because I have read four threads on it and each answered a slightly different question.

The version I want answered is the narrow one: given the method stated below, is the result within what anyone else has seen? I am not asking what it means yet.

Method, numbers and the two assumptions I am aware of making are below. If the assumptions are wrong that is more useful to me than agreement.

0 likes 3mo

hana.satoTL4 Moderator17 May 2026#2

On the opening post — agreed on the reasoning, with one qualification.

A confidence interval is a statement about a procedure rather than about this particular interval, and the practical reading — plausible values consistent with the data — is close enough for most purposes and worth knowing is an approximation.

0 likes 2mo

n.okwuosaTL231 May 2026 · edited#3

micrograms, post #1: What a confidence interval means, from scratch — that is the question, and I have not found it answered plainly anywhere I have looked. Asking about confidence interval directly, because I have read four threads on it and each answered a slightly different question. The version I want answered is the narrow one: given the method stated… Go to post

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

Confidence intervals: rather than a single point estimate, a range of plausible values. A narrow interval means precise measurement; a wide interval means measurement is imprecise. Wider intervals (more uncertainty) are honest about limitation.

That much is documented. The rest is how I have interpreted it.

9 likes in reply to #1 2mo

This topic was referenced in

Measurement error in home scales, with a worked standard deviation — a second datasetResearch Methods › Statistics · 2 replies

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