Variability among studies should be investigated

doi:10.1136/bmj.310.6994.1604a

From trainee to consultant, BMJ Group offers doctors around the world tailored information, special events, learning resources and recruitment services at every step along their career path.

... by doctors, for doctors, for patients
We are open for entries!

Online learning

BMJ Learning

High-quality CME / CPD for doctors and other healthcare professionals. BMJ Learning features hundreds of accredited, peer-reviewed learning modules in text, video, and audio formats. Find out more

Courses and Qualifications

BMJ Masterclasses

BMJ Masterclasses, led by experts, help clinicians to use the latest evidence and recent guidelines in practice and meet their CPD/CME requirements. Find out more

Exam Preparation

The leading provider of online exam preparation, helping over 167,000 healthcare professionals to pass their exams. Find out more

onExamination

Search all BMJ comment articles:

From

Limit by

Access to the full text of this article requires a subscription or payment. Please log in or subscribe below.

A Perry,
R Persaud

Senior house officer in psychiatry Consultant psychiatrist Westways, West Croydon, Surrey CR9 2RR

EDITOR,—Matthias Egger and George Davey Smith explain how pooling of smaller studies can turn out to be misleading after the subsequent publication of larger trials and suggest that meta-analyses of small trials should now be distrusted, even if their combined effect reaches significance.1 Yet they also point out that evidence from megatrials will continue to be unavailable for most medical interventions, and hence meta-analyses of smaller trials remain the only …