Evidence category
ADHD.
Child and adult ADHD — stimulants, non-stimulants, adult onset, and diagnostic thresholds.
ADHD
Stimulants reduce ADHD symptoms acutely vs placebo with effect sizes of 0.55–0.84 on teacher and clinician ratings, but the 14-month MTA advantage disappeared by 36 months, long-term functional outcomes do not differ by initial treatment assignment, and parent-teacher rating disagreement is not measurement error—it reflects situation-specific behavior across settings.
ADHD Medications and the Evidence
Guanfacine and clonidine show child clinician SMDs −0.67 and −0.71 (Cortese 2018), but atomoxetine and viloxazine carry boxed warnings for suicidal ideation. Adult lisdexamfetamine Castells 2018 SMD −1.06; bupropion Verbeeck 2017 pooled −0.50 but clinician-only ns. Adult ER-MPH Boesen 2022 investigator SMD −0.42; IR-MPH Cândido 2021 investigator MD −20.70 but participant ns. Adult GXR Iwanami 2020 Japan diff −4.28; child GXR Sallee 2009 LS-mean −5.41 to −7.88.
Adult ADHD and the Evidence
Prospective cohort studies find that childhood ADHD persistence to adulthood is low across named cohorts (Dunedin 5%, Pelotas 17.2%, E-Risk 21.9%), most adult-ADHD cases lack prospectively diagnosed childhood ADHD (Dunedin 90%, Pelotas 84.6%, E-Risk 67.5%), and after excluding substance use and other disorders, fewer than 1% of originally undiagnosed children meet late-onset criteria.