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Retrospective analyses versus RCTs: comparing like with like?

Authors Baron R, Kennes LN, Elling C

Received 27 January 2017

Accepted for publication 8 February 2017

Published 31 March 2017 Volume 2017:10 Pages 783—786


Checked for plagiarism Yes

Editor who approved publication: Dr Katherine Hanlon

Ralf Baron,1 Lieven Nils Kennes,2 Christian Elling3

1Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital of Schleswig-Holstein, Kiel Campus, Kiel, 2Department of Economics and Business Administration, University of Applied Sciences Stralsund, Stralsund, 3Grünenthal GmbH, Medical Affairs Europe and North America, Aachen, Germany

In their recent retrospective analysis assessing oxycodone/naloxone (OXN) vs. tapentadol (TAP) treatment for chronic low-back pain with a neuropathic component, Ueberall and Mueller-Schwefe1 compare their results to the findings of an earlier phase 3b/4 study.2 In our opinion, a proper comparison to the prospective, randomized, controlled, open-label study by Baron and colleagues is scientifically not appropriate. Although Ueberall and Mueller-Schwefe use the terms “prospective,” “randomly,” and “blinded” and refer to the PROBE design (prospective, randomized, open-label, blinded endpoint),3 their database study is retrospective, nonrandomized, and nonblinded with the treatment choice left to the discretion of the physicians. In this context, the use of the term “intention-to-treat (ITT) population” is inappropriate because ITT is unambiguously defined as including all randomized subjects and thus inseparable from true randomization (ICH E9).4

View original paper by Ueberall and Mueller-Schwefe.

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