The Peptide CommonsEst. May 2024
Independent. We sell nothing and are affiliated with no manufacturer or pharmacy. Every moderation action is logged in public
Topic summary

Measurement error in home scales, with a worked standard deviation — the long version

This is a generated summary. It shows the 9 most-liked posts from a topic of 106, 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.
DM
d.magalhesTL2Member Solution8 Jan 2026#9

Since Measurement error in home scales keeps coming up, it should probably be a maintained page rather than a recurring thread. I am happy to draft it if someone with more direct experience will review it.

17 likes 7mo
AC
a.coelhoTL210 Jan 2026#10

Time-to-event analysis handles differing follow-up in a way a simple proportion cannot, which is why event rates and Kaplan-Meier estimates can differ.

I have left out the parts I could not verify.

33 likes 7mo
SR
sa.rasmussenTL22 Feb 2026#24
d.magalhes, post #9: Since Measurement error in home scales keeps coming up, it should probably be a maintained page rather than a recurring thread. I am happy to draft it if someone with more direct experience will review it. Go to post

A standard deviation describes the spread of individuals and a standard error describes the precision of the mean. Quoting one where the other belongs changes the apparent result substantially.

32 likes in reply to #9 6mo
MD
methods_draftTL2Member21 Feb 2026#37

Post #33 put the caveat in the right place and I want to underline it.

Practical note on Measurement error in home scales: write down what you expect before you look. The number of times I have found what I went looking for is higher than chance would allow.

29 likes 5mo
TM
t.marchettiTL21 Mar 2026#43

Adding a small correction to the Measurement error in home scales summary above rather than a disagreement with it. The substance holds; one of the figures is out by a factor that matters.

27 likes 5mo
KL
k.laurentTL218 Mar 2026#56

Confirming post #53 from a second method, which matters more than confirming it from a second person.

Survivorship in a self-reporting population biases every aggregate produced from it, and the bias is in the flattering direction.

Two people can read the same figure differently here and both be reasonable.

27 likes 4mo
TH
TL4_HalvorsenTL4Leader · Journal club9 Apr 2026 · edited#74

This follows post #73 rather than contradicting it.

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.

31 likes 4mo
OL
o.lindgrenTL2Regular26 Apr 2026#88

Post #84 describes the usual case. This is about the unusual one.

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.

Reading it back, the second half matters more than the first.

31 likes 3mo
PD
p.dialloTL24 May 2026#95
e.almeida, post #48: One caution on Measurement error in home scales: everything above assumes the underlying documentation is what it claims to be. That assumption is doing real work and is rarely stated. Go to post

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.

It is a small point and it changes the answer, which is an awkward combination.

27 likes in reply to #48 3mo

Read the full topic (106 posts)

Suggested topics

TopicParticipantsRepliesViewsActivity
[2026 update] Correlation in a self-tracked dataset: what it can support
Posting this under the heading it deserves: Correlation in a self-tracked dataset: what it can support Everything below is what sits behind that. Posting a small dataset on Correlation. It is mine, it is…
GTARLS 2 31k 6h
What a confidence interval means, from scratch — the long version
The question in the title: What a confidence interval means, from scratch — the long version I will give what I have already checked below so nobody repeats it. Asking about confidence interval directly,…
OVTSAWCEBW+16 20 2.3k 8mo
About the Statistics category
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…
SLJMBVCAV+4 8 2.3k 7mo
Multiplicity when you track fifteen variables
Multiplicity when you track fifteen variables — setting out what I have, and where I think it stops being reliable. Asking about multiplicity directly, because I have read four threads on it and each answered…
JATNNA 2 60k 11mo
Measurement error in home scales, with a worked standard deviation — a second dataset
Measurement error in home scales, with a worked standard deviation — a second dataset — setting out what I have, and where I think it stops being reliable. Posting a small dataset on Measurement error in home…
AKKSA 2 13k 7mo

Related topics — sharing the tags number needed to treat, worked example, heterogeneity

TopicParticipantsRepliesViewsActivity
Revisiting: Journal club: SURMOUNT-OSA and a hard endpoint in a soft field
Revisiting: Journal club: SURMOUNT-OSA and a hard endpoint in a soft field — setting out what I have, and where I think it stops being reliable. Collecting what is known about SURMOUNT-OSA in one place,…
FPHMLPAAVB+108 122 52k 7d
Second pass at: Absence of evidence and evidence of absence
On the subject in the title: Second pass at: Absence of evidence and evidence of absence Working notes rather than a conclusion. Two things I would like separated before anyone answers on Absence of evidence,…
SLMFEMRHSR+50 55 18k 16h
What to include when your question involves a chromatogram — one year on
Asking directly, because I could not find a straight answer: What to include when your question involves a chromatogram — one year on Question in the title. Context below, and I have tried to include the…
HKCETVNKO+69 75 862 14d
Semaglutide in people without diabetes: what the evidence base looks like
Semaglutide in people without diabetes: what the evidence base looks like Writing it up because I had to work it out twice and would rather nobody else did. What changes if the standard account of semaglutide…
GCSDNVMHN+2 6 18k 17mo
Coming back to: Prediction intervals and why they are more honest than confidence intervals
Prediction intervals and why they are more honest than confidence intervals Writing it up because I had to work it out twice and would rather nobody else did. Prediction intervals — I have the observation and…
TDIBB 2 65 22mo