Patient flow chart. (a) Five eligible patients did not enrol because teacher consent was not obtained. (b) Two patients withdrew before commencing; they were under guardianship of the Department of Community Services, which withdrew consent. A third patient changed stimulant after consenting to the trial and therefore did not take trial medication. (c) One patient decided to withdraw at end of week 3 as they were confident which period was active and decided they would prefer to be on medication for exams. (d) A fifth participant withdrew toward the end of the study (after week 4), however the reason is uncertain.