Topic summary

Designing a personal experiment that could change your mind — one year on

Research Methods › N-of-1 designs effect size data table worked example

This is a generated summary. It shows the 9 most-liked posts from a topic of 81, 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.

s.bergstromTL229 Jan 2026#6

Picking up post #3: that is the part I would want checked first.

Record everything that changed, not just the intervention. Personal experiments are confounded by life, and the confounders are only recoverable if they were written down.

28 likes 6mo

s.hartmannTL24 Mar 2026 · edited#17

ch.correia, post #9: Post #7 and I disagree about the size of the effect, not about the direction. Generalisability: a robust n-of-1 result applies to you. It does not tell you much about whether the effect generalises to others similar to you, much less to people different from you. Go to post

A washout period between conditions is what stops one bleeding into the next, and its length should be set by the half-life rather than by convenience.

27 likes in reply to #9 5mo

slow_titratorTL2Regular18 Mar 2026#22

Duration should be set by how long an effect would take to appear rather than by patience. Stopping early is the commonest reason a personal experiment answers nothing.

That is what the documentation says. What happens in practice is usually close.

29 likes 4mo

b.petrovTL224 Apr 2026 · edited#37

Post #34 is right about the mechanism and I think understates the practical bit.

Write down what you would accept as evidence that it did not work, before starting. That one sentence turns an anecdote into an experiment.

It is worth stating the boring hypothesis before the interesting one.

30 likes 3mo

diluent_watchTL2Member8 May 2026 · edited#43

The interesting personal experiments are the ones where the answer was no. They are also the ones least likely to be written up.

32 likes 3mo

r.scholtenTL2Member17 May 2026#47

Checked the Designing a personal experiment claim against the primary source this morning. It survives, with a narrower scope than the version quoted here. Posting the narrower scope.

24 likes 2mo

no.silvaTL223 May 2026 · edited#50

Post #49 answers the question as asked. The question underneath it is different.

A washout period between conditions is what stops one bleeding into the next, and its length should be set by the half-life rather than by convenience.

33 likes 2mo

t.abubakarTL27 Jun 2026#57

Duration should be set by how long an effect would take to appear rather than by patience. Stopping early is the commonest reason a personal experiment answers nothing.

25 likes 2mo

a.silvaTL218 Jun 2026#62

I think the Designing a personal experiment question is answerable and has not been answered, which is a more optimistic position than most of this thread.

31 likes 1mo

Read the full topic (81 posts)

This topic was referenced in

An ABAB design with a data table and honest limitations — a second datasetResearch Methods › N-of-1 designs · 118 replies
Second pass at: Designing a personal experiment that could change your mindResearch Methods › N-of-1 designs · 44 replies

Suggested topics

Topic	Participants	Replies	Views	Activity
Washout with a one-week half-life: the arithmetic — does this still hold? Research Methods › N-of-1 designs confounding data table worked example Solved Washout with a one-week half-life: the arithmetic — does this still hold? — that is the question, and I have not found it answered plainly anywhere I have looked. Washout: setting out the arithmetic in full,…	+41	45	12k	1d
Pre-registering a personal experiment, seriously Research Methods › N-of-1 designs worked example data table effect size confounding Pre-registering a personal experiment, seriously — setting out what I have, and where I think it stops being reliable. A narrow question about pre-registering a personal experiment, deliberately narrow,…	+96	119	58k	14mo
Blinding yourself: practical methods and their limits — the long version Research Methods › N-of-1 designs worked example effect size confounding data table Blinding yourself: practical methods and their limits — the long version Writing it up because I had to work it out twice and would rather nobody else did. A narrow question about Blinding yourself,…	+7	11	1.8k	22h
An ABAB design with a data table and honest limitations — a second dataset Research Methods › N-of-1 designs confounding effect size data table worked example Solved On the subject in the title: An ABAB design with a data table and honest limitations — a second dataset Working notes rather than a conclusion. Posting a small dataset on ABAB design. It is mine, it is…	+106	118	25k	4mo
Why most self-reports here are not experiments, and that is fine Research Methods › N-of-1 designs confounding worked example data table effect size Closed Why most self-reports here are not experiments, and that is fine — that is the question, and I have not found it answered plainly anywhere I have looked. A question about what a single-person experiment can…		2	46k	11mo

Related topics — sharing the tags effect size, data table, worked example

Topic	Participants	Replies	Views	Activity
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. Two things I would like separated before anyone answers on…		2	12k	18mo
Why cagrilintide alone is discussed so much less than in combination — does this still hold? Compounds › Cagrilintide & amylin analogues cagrisema randomised trial cagrilintide effect size Solved Under review Why cagrilintide alone is discussed so much less than in combination — does this still hold? — that is the question, and I have not found it answered plainly anywhere I have looked. Cagrilintide alone:…	+27	31	1.2k	22h
Bioimpedance and hydration: why the number moves Outcomes › Body composition lean mass loss data table DXA bioimpedance Bioimpedance and hydration: why the number moves — setting out what I have, and where I think it stops being reliable. I have spent a fortnight trying to pin bioimpedance and hydration down and I want to set…	+62	70	13k	23d
Titrating on tolerability rather than on the calendar Practice › Dosing & titration dose reduction tirzepatide worked example missed dose On the subject in the title: Titrating on tolerability rather than on the calendar Working notes rather than a conclusion. An honest uncertainty about titrating on tolerability rather than a disguised…		2	31k	13mo
What pooling buys you and what it destroys Evidence › Meta-analyses publication bias risk of bias meta-analysis heterogeneity Solved The question in the title: What pooling buys you and what it destroys I will give what I have already checked below so nobody repeats it. The question about pooling buys that I actually want answered is the…	+74	83	6.6k	8mo