The relationship of childhood adversity and migraine and the value of prospective studiesThe first report of a link between childhood maltreatment and recurrent headache appeared over 30 years ago, in a small study of adult women recounting a history of childhood sexual abuse. 1 Several studies confirming an association of headache and contact (sexual and/or physical) abuse followed, 2-5 but it was another 20 years before the scope of investigation of this particular association was expanded to include emotional childhood abuse, as well as exposure to traumatizing household dysfunction (family member substance abuse, mental illness, incarceration, witnessing maternal battering, and parental separation/divorce). 6 The results from the 2010 analysis of the large, landmark Adverse Childhood Experiences (ACE) study dataset demonstrated that frequent headache was associated with each of the eight types of ACEs evaluated, particularly emotional abuse, and that there was a dose-response relationship between cumulative ACE score and prevalence/risk of headache in adults. 6 The American Migraine Prevalence and Prevention study that followed in 2015, 7 was the first publication to use International Classification of Headache Disorders criteria in a nationally representative sample evaluating the maltreatment-headache link while also controlling for depression and anxiety. The queries on maltreatment only encompassed emotional neglect, emotional abuse, and sexual abuse, but, nevertheless, results demonstrated that, compared with adults with episodic tension-type headache, adults with migraine were more likely to recall abuse and neglect in childhood. The American Migraine Prevalence and Prevention study, 7 most preceding it, 1-6 and two large adult population-based studies that followed it, 8,9 corroborated the associations of adverse childhood events with adult headache/migraine. All, however, have been limited by their retrospective design, and with this the looming specter of recall bias, particularly How to cite this article: Tietjen GE. The relationship of childhood adversity and migraine and the value of prospective