Questions · Separation from Cardiopulmonary Bypass
7 questions, 0 approved. Approve them one at a time — a quiz shows nothing you have not.
Recall — derived from a kept point
CHEETAH was stopped for futility. What does that specifically mean, and how is it different from a trial stopped for harm or one that simply reports a negative result?
Answer: Stopping for futility means a preplanned interim analysis showed that continuing to the planned sample size was very unlikely to demonstrate the hypothesised benefit — so further enrolment would expose patients to an intervention and a trial burden with no realistic prospect of a positive answer. It is not a finding of harm; CHEETAH found no significant difference in rates of hypotension or cardiac arrhythmias either. It differs from an ordinary negative trial in that the confidence intervals are wider than planned, so it is better read as failing to demonstrate benefit than as proving equivalence.
Futility stopping limits what you can conclude in both directions. It is evidence against a large benefit, not proof of no effect.
Source claim: CHEETAH was stopped for futility after 506 patients were enrolled, with no significant difference between levosimendan and placebo in rates of hypotension or cardiac arrhythmias.
CHEETAH trial, NEJM 2017
recall · CA-3 · phrased by llm
Besides mortality, which secondary outcomes did CHEETAH examine, and what did they show?
Answer: Duration of mechanical ventilation (median 19 hours with levosimendan versus 21 with placebo), ICU stay (median 72 versus 84 hours) and hospital stay (median 14 versus 14 days). None reached statistical significance, although the ICU stay difference of -12 hours had a confidence interval of -21 to 2 hours and a P value of 0.09, which is the kind of near-miss that gets over-quoted.
A P of 0.09 on a secondary outcome in a trial stopped for futility is a hypothesis, not a finding.
Source claim: In CHEETAH there were no significant differences between levosimendan and placebo in duration of mechanical ventilation (median 19 versus 21 hours), ICU stay (median 72 versus 84 hours) or hospital stay (median 14 versus 14 days). The ICU stay median difference was -12 hours (95% CI -21 to 2, P=0.09).
CHEETAH trial, NEJM 2017
recall · CA-3 · phrased by llm
The point with one number taken out. No model wrote any of this: the stem is the sentence you reviewed, minus a digit, and the paper it came from is named beneath it.
Open prompts
How would you teach this to a CA-1 in two minutes?
open · CA-3 · phrased by derived
Where does the evidence for this actually stop?
open · CA-3 · phrased by derived
What would you do differently in a resource-limited setting?
open · CA-3 · phrased by derived
Defend the alternative you decided against.
open · CA-3 · phrased by derived
Questions only — nothing here asserts anything, which is why a model is allowed to phrase them. Where no model was reachable these are the level defaults.