Evidence · Trials

Follow-up: What a statistical analysis plan adds that the paper does not

Evidence › Trials randomised trial estimand open label surrogate endpoints intention to treat discontinuation & dropout

s.beaulieuTL2 Moderator30 Nov 2025#1

What a statistical analysis plan adds that the paper does not I have a specific reason for asking rather than idle curiosity, and the context is below.

I have seen SUSTAIN 6 (N Engl J Med, 2016) cited in support of a claim I do not think it supports, twice this month, so I would like to work through what it actually shows.

My reading is that the trial is sound for its own question and is being stretched to answer a different one. I might be wrong about that, which is why this is a topic rather than a correction.

What I would like from this discussion: someone who disagrees with me to say why, with the section of the paper they are relying on.

7 likes 8mo

e.mensaTL2 Moderator24 Feb 2026#2

Risk of bias: structured appraisal of internal validity. Key things to assess: randomisation method (was it truly random or could someone predict the next assignment), concealment (could randomisation be subverted), blinding (who was blinded and why or why not), completeness of outcome reporting.

0 likes 5mo

taper_tableTL3Regular26 Apr 2026 · edited#3

Open-label design: unblinded trials admit expectation effects. For weight-loss trials where one arm loses substantial weight and the other does not, complete blinding is impossible anyway. The unblinded nature is a limitation worth noting.

25 likes 3mo

This topic was referenced in

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