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Tom Jefferson – CEBM

Refining the E in EBM: Developing Better Evidence
Monday July 15th- 15:30

Senior Associate Tutor, Department of Continuing Education


The session will briefly explore the evidence of distortion introduced into systematic reviews by the the inclusion of data sources affected by hard to detect reporting bias. And explore the question of whether given the evidence of distortion of trial reporting we should ignore evidence from journal articles This is because by the law of Garbage In Garbage Out, whatever is produced in our reviews will be systematically assembled and synthesised garbage. The session will also discuss practical ways to change the evidence base of reviews of pharmacuticals interventions and barriers to such actions. Discussion will be maximised and frontal input will be minimal.

Tom Jefferson is the first author of the first systematic review carried out solely on regulatory submissions by industry for a family of drugs as illustrated in the James Lind Library Timeline.

For background attendees are invited too read the 800-worder Jefferson T and Jørgensen L. Redefining the ‘E’ in EBM. BMJ Evid Based Med. 2018 Mar 9;23:46-47.

There is a Spanish language translation of this article available as a data supplement.

There is an Italian language version of this article here”


Tom Jefferson is a physician, researcher and campaigner for access to randomised controlled trial data.

For many years, Tom was denied access to regulatory data on which to base the Cochrane reviews he co-authors. At present, Tom is the first author of the only Cochrane review based solely on unpublished on regulatory data. The review of Neuraminidase inhibitors for preventing and treating influenza was seen as a major methodological development in the field of evidence-based medicine. The review challenged opinion across the regulatory, industrial and policy arenas, and has since been added as a landmark within the James Lind Library. It was the most accessed review in the Cochrane Library in 2014. The review was published in April 2014, both on the Cochrane Library and the BMJ, and was the culmination of a 4-year campaign to obtain a complete set of previously unseen 107 clinical study reports.

July 15 - 17 2019
Registration Open

2019 Call for Abstracts
Deadline April 14th