Editorial
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Meta-Anal. Feb 26, 2015; 3(1): 1-3
Published online Feb 26, 2015. doi: 10.13105/wjma.v3.i1.1
Why meta-analyses are important for complementary and alternative medicine research
Holger Cramer
Holger Cramer, Department of Internal and Integrative Medicine, Kliniken Essen-Mitte, Faculty of Medicine, University of Duisburg-Essen, 45276 Essen, Germany
Author contributions: Cramer H solely contributed to this editorial.
Supported by Rut- and Klaus-Bahlsen Foundation, Germany.
Conflict-of-interest: The supportive foundations had no influence on the content of this editorial.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Holger Cramer, PhD, MSc, Department of Internal and Integrative Medicine, Kliniken Essen-Mitte, Faculty of Medicine, University of Duisburg-Essen, Am Deimelsberg 34a, 45276 Essen, Germany. h.cramer@kliniken-essen-mitte.de
Telephone: +49-201-17425015 Fax: +49-201-17425000
Received: October 20, 2014
Peer-review started: October 20, 2014
First decision: November 27, 2014
Revised: December 3, 2014
Accepted: December 29, 2014
Article in press: December 31, 2014
Published online: February 26, 2015
Core Tip

Core tip: The research evidence from single trials on complementary and alternative medicine (CAM) is often limited by small sample sizes, unclear methodology, and inadequate statistics. Qualitative systematic reviews still have to deal with the same problems as individual trials as they can only rely on the original reports. While meta-analyses still are limited by the methodological shortcomings of the included, they can deal with two common problems of CAM trials: inadequate statistics that rely on within-group comparisons and small underpowered sample sizes.