We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Editor's Correspondence |

Ignoring Study Design Heterogeneity in Meta-analyses

J. Jaime Caro, MDCM, FRCPC; James G. Xenakis, BS; Krista F. Huybrechts, MS
Arch Intern Med. 2006;166(18):2046. doi:10.1001/archinte.166.18.2046-a.
Text Size: A A A
Published online


The meta-analysis by Lafuente-Lafuente et al1 of treatments for maintaining sinus rhythm addresses a key aspect of the management of atrial fibrillation (AF), but the authors failed to deal with the enormous heterogeneity in the designs of the studies.

Patients with chronic atrial fibrillation differ substantially from those with the paroxysmal condition in their ability to maintain sinus rhythm, yet the populations studied varied regarding the type of AF and even in the definitions of “paroxysmal” and “chronic” used to classify patients. They also differ on the methodological issue of whether patients need to be in sinus rhythm at the time of randomization. Thus, pooling the data assumes that patients who were in sinus rhythm for several months after a paroxysm of AF2 are comparable with those cardioverted only a couple of hours prior to randomization.3 Moreover, some studies do not count early recurrences2,4 and some allow patients to be cardioverted again, while others count every recurrence no matter how soon it occurs.

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

First Page Preview

View Large
First page PDF preview





Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

0 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
PubMed Articles

The Rational Clinical Examination: Evidence-Based Clinical Diagnosis
Accuracy of Clinical Findings in Endemic Areas

The Rational Clinical Examination: Evidence-Based Clinical Diagnosis
Data Analysis and Statistical Methods