Vertessen K, Luman M, Staff A, et al. - Methylphenidate (MPH) is superior to placebo in treating attention-deficit/hyperactivity disorder (ADHD) symptoms and a wide range of neurocognitive functions, however, the magnitude of the effects varies greatly between functions. The findings emphasise the need of taking into account both neurocognitive and symptomatic elements of ADHD in therapeutic practice.

• Placebo-controlled trials were involved that examined MPH dosing effects on neurocognitive functions in children (5–18 years) diagnosed with ADHD.

• Thirty-one studies met the inclusion criteria, involving 804 ADHD children. MPH has a positive impact on all neurocognitive functions.

• Significant linear dosing effects were identified for ADHD symptoms and lower-order neurocognitive skills (baseline speed, variability in responding, non-executive memory), with higher improvement in functioning with increasing dose.

• There were no dosing effects reported for higher-order neurocognitive functions (executive memory, inhibitory control and cognitive flexibility).

• MPH had no negative effects on any of the investigated functions.