Gender- and age-specific estimates of migraine prevalence (North America) based on 18 population studies that used International Headache Society (IHS) diagnostic criteria. (Scher A, Stewart W, Lipton R. Migraine and headache: A meta-analytic approach. In: Crombie I, ed. Epidemiology of Pain. Seattle, Wash: IASP Press; 1999:159–170.) Source: Chapter 17. Epidemiology of Headaches, Principles & Practice of Pain Medicine, 2e Citation: Warfield CA, Bajwa ZH. Principles & Practice of Pain Medicine, 2e; 2004 Available at: https://accessanesthesiology.mhmedical.com/DownloadImage.aspx?image=/data/books/warf/warf_c017f002.gif&sec=40431231&BookID=411&ChapterSecID=40429801&imagename= Accessed: October 24, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved