The primary purpose of this study is to identify whether, after adjustment for confounders via stratification on a propensity score and adjustment for calendar year, the combined endpoint consisting of #1 to #4 (1. switching back to Concerta, 2. changing the use of immediate release [IR] methylphenidate, 3. beginning a new attention deficit hyperactivity disorder [ADHD] medication, or 4. stopping both Concerta and the long acting [LA] methylphenidate {authorized generic [AG] methylphenidate or equivalent generic [EG] methylphenidate} that was begun on the index date), differs between participants who switch from branded Concerta to the EG formulations versus participants who switch from branded Concerta to the AG formulation.