Meta-Analysis
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Meta-Anal. Feb 22, 2019; 7(2): 31-50
Published online Feb 22, 2019. doi: 10.13105/wjma.v7.i2.31
Misclassification of smoking habits: An updated review of the literature
Janette S Hamling, Katharine J Coombs, Peter N Lee
Janette S Hamling, RoeLee Statistics Ltd., 17 Cedar Road, United Kingdom
Katharine J Coombs, Peter N Lee, P.N. Lee Statistics and Computing Ltd., Sutton SM2 5DA, United Kingdom
Author contributions: Hamling JS and Lee PN planned the study; Coombs KJ carried out the literature searches, assisted by the other authors; Hamling JS carried out the data entry, assisted by Lee PN; Hamling JS carried out the statistical analyses along lines discussed and agreed with Lee PN; Lee PN drafted the paper which was critically reviewed by the other authors.
Conflict-of-interest statement: All the authors are long-term consultants to various tobacco companies and organizations.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
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/
Corresponding author: Peter N Lee, MA, Director, Senior Statistician, P.N. Lee Statistics and Computing Ltd., 17 Cedar Road, Sutton SM2 5DA, United Kingdom. peterlee@pnlee.co.uk
Telephone: +44-20-6428265 Fax: +44-20-8642135
Received: November 29, 2018
Peer-review started: November 29, 2018
First decision: December 15, 2018
Revised: January 21, 2019
Accepted: January 21, 2019
Article in press: January 21, 2019
Published online: February 22, 2019
Processing time: 85 Days and 15 Hours
Core Tip

Core tip: We update a meta-analysis of evidence on accuracy of reported smoking, using cotinine as a marker. From 200+ studies, we estimated various misclassification rates. True smokers represented 3.00% (2.45%-3.54%) of reported never smokers and 10.92% (9.23%-12.61%) of reported ex-smokers. Reported never and ex-smokers formed 5.70% (3.20%-8.20%) and 8.93% (6.57%-11.29%) of true smokers. Falsely claiming never smoking was extremely common in Asian women. Rates of falsely claiming quitting were high in pregnant women and diseased individuals advised to quit. Smoking misclassification causes overestimation of true passive smoking relationships, a problem exacerbated by increasing misclassification rates in recently published studies.