Outcomes · Body composition

Revisiting: Bioimpedance and hydration: why the number moves

Outcomes › Body composition data table DXA bioimpedance

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Solved by l.aaltonen in post #3

Where a facility reports a precision figure for its own machine, that number is more useful than any published average. This is the sort of thing the wiki should carry and currently does not.

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s.salgadoTL212 May 2026#1

Posting this under the heading it deserves: Revisiting: Bioimpedance and hydration: why the number moves Everything below is what sits behind that.

I have spent a fortnight trying to pin Bioimpedance and hydration down and I want to set out where I have got to, because I suspect the honest answer is duller than the thread this will produce.

What I have: a consistent observation across a small number of cases, collected the same way each time. What I do not have: any controlled comparison, or any reason to think my cases are representative.

The specific question is whether the pattern survives once the obvious confounder is removed. I cannot remove it with what I have.

0 likes 3mo

b.adeyemiTL24 Jun 2026#2

The opening post describes the usual case. This is about the unusual one.

Report the method with the number, always. A composition figure without the method is not comparable to anything, including your own previous figure.

A partial answer, offered because a partial answer beats none.

1 like 2mo

l.aaltonenTL3Regular Solution19 Jun 2026 · edited#3

b.adeyemi, post #2: The opening post describes the usual case. This is about the unusual one. Report the method with the number, always. A composition figure without the method is not comparable to anything, including your own previous figure. A partial answer, offered because a partial answer beats none. Go to post

Where a facility reports a precision figure for its own machine, that number is more useful than any published average.

This is the sort of thing the wiki should carry and currently does not.

10 likes in reply to #2 1mo

This topic was referenced in

Ultrasound and skinfolds: operator dependence in practice — what changed sinceOutcomes › Body composition · 37 replies

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