PMean » Early stopping http://blog.pmean.com A blog about statistics, evidence-based medicine, and research ethics Sat, 22 Jun 2024 17:10:26 +0000 en-US hourly 1 https://wordpress.org/?v=3.7.41 PMean: Slapping the word “pilot” on a failed study http://blog.pmean.com/failed-study/ http://blog.pmean.com/failed-study/#comments Sun, 03 Mar 2019 16:23:50 +0000 http://blog.pmean.com/?p=1780 This page is moving to a new website.

]]> http://blog.pmean.com/failed-study/feed/ 0 Recommended: Safeguarding Patients in Clinical Trials with High Mortality Rates http://blog.pmean.com/safeguarding/ http://blog.pmean.com/safeguarding/#comments Wed, 02 Dec 2015 22:01:49 +0000 http://blog.pmean.com/?p=571 This is an article the I would trot out if anyone tried to argue that a Data Safety and Monitoring Board should, like the investigators, be blinded as to treatment status during their deliberations.

BRADLEY D. FREEMAN, ROBERT L. DANNER, STEVEN M. BANKS, and CHARLES NATANSON “Safeguarding Patients in Clinical Trials with High Mortality Rates”, American Journal of Respiratory and Critical Care Medicine, Vol. 164, No. 2 (2001), pp. 190-192. doi: 10.1164/ajrccm.164.2.2011028. Available at http://www.atsjournals.org/doi/full/10.1164/ajrccm.164.2.2011028.

]]> http://blog.pmean.com/safeguarding/feed/ 0 Recommended: Predicting clinical trial results based on announcements of interim analyses http://blog.pmean.com/predicting-trial-results/ http://blog.pmean.com/predicting-trial-results/#comments Sun, 06 Apr 2014 22:34:38 +0000 http://blog.pmean.com/?p=222 If you’ve ever been involved with interim reviews of clinical trials on a DSMB (Data Safety and Monitoring Board), you will be warned about the importance of confidentiality. There are two big reasons for this. First, leaking of interim trial results could lead to insider trading. News that the trial is going well would lead to a jump in stock prices and news that the trial is going poorly would lead to a dip in stock prices. If someone gets early news from the DSMB, they could profit from that inside information.

The second reason that you need confidentiality is that the company conducting the trial might make changes to the trial based on information at the interim review. This might involve speeding up recruiting, changing the entry criteria, or other mid-stream protocol changes. These changes, if based on interim data results, could affect the operating characteristics of the study. One possibility might be an inflation of the Type I error rate.

It turns out that a DSMB does not need to release ANY information and still provide partial information about the probability of success of the clinical trial. If the DSMB recommends that a trial continue at one of its meeting, you have a bit of information, because the criteria for early stopping for futility, for example, was not met. This article talks about this and offers a real world example.

Broglio KR, Stivers DN, Berry DA. Predicting clinical trial results based on announcements of interim analyses. Trials. 2014;15(1):73. doi:10.1186/1745-6215-15-73. Available at: http://www.trialsjournal.com/content/15/1/73

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