 Using a proprietary insurance health claims database, Eli Lilly and Company has contracted with an external party to conduct a retrospective cohort study of health claims for the time period from 1 January 2003 through 31 December 2006 with follow-up of patients through 30 June 2007. This study will evaluate the potential association between atomoxetine and cerebrovascular events. In this study, the incidence of selected cerebrovascular outcomes as represented in health claims data among adult patients who initiate therapy with atomoxetine will be estimated. In particular the study will focus on cerebrovascular accident CVA and transient ischemic attack TIA as the outcomes of interest. The incidence for each outcome among atomoxetine initiators will then be compared to the incidence in a cohort of similar patients who initiate stimulant treatment and an age and gender-matched general population cohort. The atomoxetine and stimulant-initiating cohorts will be matched on a broad variety of variables, including age, gender, diagnoses, medication use, and healthcare utilization through the use of propensity score matching in order to minimize the influence of confounding by indication. The analysis will include the cohorts atomoxetine and stimulant initiators from a previous completed study with increased follow-up time 1 January 2003 through 30 June 2007 and accrue new atomoxetine and stimulant ADHD medication initiators over a 2 year period, so that the study will represent initiators between January 1, 2003 and December 31, 2006 with follow-up through June 30, 2007. 