The full content of Annals is available to subscribers

Subscribe/Learn More  >
Ideas and Opinions |

How Should Results from Completed Studies Influence Ongoing Clinical Trials?: The CAFA Study Experience

Andreas Laupacis, MSc, MD; Stuart J. Connolly, MD; Michael Gent, DSc; Robin S. Roberts, MSc; John Cairns, MD; Campbell Joyner, MD, CAFA Study Group
[+] Article, Author, and Disclosure Information

Grant Support: By grant 9846 from the Medical Research Council of Canada and by DuPont Canada Inc.

Requests for Reprints: Andreas Laupacis, MSc, MD, Clinical Epidemiology Unit, Loeb Research Institute, Ottawa Civic Hospital, 1053 Carling Avenue, Ottawa, Ontario K1Y 4E9.

Current Author Addresses: Dr. Laupacis: Clinical Epidemiology Unit, Loeb Research Institute, Ottawa Civic Hospital, 1053 Carling Avenue, Ottawa, Ontario K1Y 4E9.

Dr. Connolly: Hamilton General Hospital, 237 Barton Street, East, Hamilton, Ontario L8L 2X2.

Professors Gent and Roberts: Hamilton Civic Hospital Research Centre, 711 Concession Street, Hamilton, Ontario L8V 1C3.

Dr. Cairns: McMaster University Medical Centre, 1200 Main Street, Hamilton, Ontario L8N 3Z5.

Dr. Joyner: Sunnybrook Health Science Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5.

© 1991 American College of PhysiciansAmerican College of Physicians

Ann Intern Med. 1991;115(10):818-822. doi:10.7326/0003-4819-115-10-818
Text Size: A A A

▪ Seven randomized studies during the past 5 years have evaluated or are evaluating the efficacy of warfarin or aspirin or both in decreasing the risk of embolic events in patients with nonrheumatic atrial fibrillation. By March 1990, two of the studies had been published, both of which showed a statistically significant decrease in embolic events in patients treated with warfarin and a low rate of major bleeding events. The investigators associated with the other ongoing studies were forced to consider how these results should affect the decision to recruit and continue follow-up of patients in their own studies.

The Steering Committee of the Canadian Atrial Fibrillation Anticoagulation (CAFA) study thought the newly published results from other studies were valid, clinically important, and generalizable. The committee considered the following options for the CAFA study: continue patient recruitment as planned, provide the data available in CAFA to its External Safety and Efficacy Monitoring Committee for analysis to determine whether the CAFA data already showed a benefit of warfarin, stop patient recruitment but continue to follow patients in the group to which they were assigned, stop the trial immediately and perform a final analysis, and attempt to perform a meta-analysis of all data available from all trials. The Steering Committee of CAFA decided that the evidence of benefit with warfarin, from the two published studies, was sufficiently compelling as to stop recruitment into CAFA without any preliminary examination of the CAFA data.





Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).


Submit a Comment/Letter
Submit a Comment/Letter

Summary for Patients

Clinical Slide Sets

Terms of Use

The In the Clinic® slide sets are owned and copyrighted by the American College of Physicians (ACP). All text, graphics, trademarks, and other intellectual property incorporated into the slide sets remain the sole and exclusive property of the ACP. The slide sets may be used only by the person who downloads or purchases them and only for the purpose of presenting them during not-for-profit educational activities. Users may incorporate the entire slide set or selected individual slides into their own teaching presentations but may not alter the content of the slides in any way or remove the ACP copyright notice. Users may make print copies for use as hand-outs for the audience the user is personally addressing but may not otherwise reproduce or distribute the slides by any means or media, including but not limited to sending them as e-mail attachments, posting them on Internet or Intranet sites, publishing them in meeting proceedings, or making them available for sale or distribution in any unauthorized form, without the express written permission of the ACP. Unauthorized use of the In the Clinic slide sets will constitute copyright infringement.


Buy Now for $42.00

to gain full access to the content and tools.

Want to Subscribe?

Learn more about subscription options

Related Articles
Related Point of Care
Topic Collections
PubMed Articles
Forgot your password?
Enter your username and email address. We'll send you a reminder to the email address on record.