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Conditional PowerHow Likely Is Trial Success?

To identify the key insights or developments described in this article
1 Credit CME

Because of the costs and potential risks to participants, clinical trials should be initiated or continued only when there is a reasonable chance the results will improve clinical care or represent important new knowledge. In 2021, McNamee et al1 reported the results of a randomized clinical trial evaluating the therapeutic benefit of lower tidal volume ventilation coupled with extracorporeal carbon dioxide removal compared with standard ventilatory support in patients with acute hypoxemic respiratory failure. During a pause in recruitment for investigation of a severe adverse event, the independent data monitoring and ethics committee (DMC) made a recommendation to stop the trial early for futility, based on the feasibility of future recruitment and the low likelihood of eventual trial success. The DMC used a conditional power calculation to show that even under the most optimistic assumptions of treatment benefit, the trial had only a 44% chance of demonstrating a statistically significant benefit from the intervention on 90-day all-cause mortality.1

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Article Information

Corresponding Author: Benjamin R. Saville, PhD, Berry Consultants LLC, 3345 Bee Caves Rd, Ste 201, Austin, TX 78746 (ben@berryconsultants.net).

Published Online: January 23, 2023. doi:10.1001/jama.2022.25080

Conflict of Interest Disclosures: None reported.

References
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