{"groups":[{"description":"Participant previously had acute lymphoblastic leukemia or brain tumor to be treated with Methylphenidate or Placebo - Administered 1 capsule each day for 1 week, .3 mg/kg dose.","id":"FG000","title":"Participant With Attention Deficit"}],"periods":[{"dropWithdraws":[{"reasons":[{"groupId":"FG000","numSubjects":"1"}],"type":"Withdrawal by Subject"}],"milestones":[{"achievements":[{"groupId":"FG000","numSubjects":"1"}],"type":"STARTED"},{"achievements":[{"groupId":"FG000","numSubjects":"0"}],"type":"COMPLETED"},{"achievements":[{"groupId":"FG000","numSubjects":"1"}],"type":"NOT COMPLETED"}],"title":"Overall Study"}],"preAssignmentDetails":"Only 1 patient was enrolled in this study. This patient completed baseline assessment, but withdrew from the study before beginning the medication trial. No medications/placebo were administered."}