genuine question about TRIUMPH that I am slightly embarrassed to ask
Trying to get a straight answer on this: genuine question about TRIUMPH that I am slightly embarrassed to ask.
Why comparing across trials almost never works, with the specific failure modes.
Different populations: an obesity programme and a diabetes programme enrol different people with different baseline characteristics. Different endpoints: body weight change, glycaemic control and cardiovascular events are not convertible. Different durations: 68 weeks and 72 weeks are not the same, and the curves have not flattened by either.
Different analysis populations: one paper reports intention-to-treat, another emphasises completers. Different support: some trial designs include structured lifestyle contact that no member of this board receives.
Stack those and the "X beats Y" tables that circulate here are comparing five things at once and attributing the difference to the molecule.
How to read one of these papers in fifteen minutes, in the order that actually helps.
Start with the registered protocol and check the primary endpoint against what is reported. Then the methods: who was included, what the comparator was, how long the randomised phase ran. Then the discontinuation numbers, which are a tolerability result and are usually in a supplementary table.
Only then the efficacy figure, and read the interval rather than the point estimate. Finish with the limitations section, which is where the authors say what they actually think.
Fifteen minutes, and you will know more than any thread summarising it.
Argued for a week about a result and then read the limitations section, which conceded most of my opponent’s point.
Not medical advice, obviously, and nothing here is approved for human use. One person with a spreadsheet.
best — the order this archive was captured in
Open-label extensions lose their randomisation. Anybody still enrolled at week 104 is a selected group and the numbers describe that group.
What did the confidence interval look like?
the confidence interval is the finding, the point estimate is the headline
the confidence interval is the finding, the point estimate is the headline
Agreed. And the interval, not the point estimate, is what the trial actually established.
Correcting myself upthread: I gave the completer figure and labelled it intention-to-treat.
a mean is not a promise
trial populations get support that nobody on this board gets
Careful with that mean. The distribution around it was wide enough that it describes very few individual participants.
Started keeping the trial identifiers straight in a note file because I kept mixing up two programmes in the same sentence.
Disagree — that figure is from the diabetes programme and you are quoting it as an obesity endpoint.
Spent an evening with the appendix tables and found the subgroup detail that the entire thread had been speculating about.
Not convinced. Cross-trial comparison between two programmes with different populations and designs is not a comparison.
Compared myself to a trial mean for about six months before realising the trial arm had dietitian contact every fortnight.
STEP is semaglutide obesity, SURMOUNT is tirzepatide obesity, they are not interchangeable
discontinuation rate is a result, not a footnote
Which trial, and which arm?
Push back: an open-label extension tells you about the people who stayed. That is a different question.
Quoted a figure here confidently, got asked whether it was ITT, went and checked, and it was not. Learned something.
Quoted a figure here confidently, got asked whether it was ITT, went and checked, and it was not.
Adding the check nobody runs — the registered protocol is public and takes two minutes to compare.
FLOW was kidney outcomes and it is the one nobody quotes
Small fix — that was the cardiovascular outcomes trial, so weight was a secondary endpoint and the population was different.
Went looking for the registered protocol to see whether the endpoint had changed. It had not, which was reassuring and worth checking.
Same. A press release is a claim about a result; the publication is the result.
That is a relative risk reduction. Quoting it without the absolute numbers overstates the case considerably.
This. Intention-to-treat versus completer analysis routinely moves the headline by several points.
[removed by moderator]
That is the 68-week readout, not the 72-week one. Different trial, different duration.
Is that intention-to-treat or completers?
The discontinuation numbers were the most useful thing in the paper for me and they were in a supplementary table.
- 1Open-label extensions lose their randomisation. Anybody still enrolled at…9 comments in this branch · started by u/anders_karlsen
- 2Disagree — that figure is from the diabetes programme and you are quoting it…8 comments in this branch · started by u/milan_villalobos