Twenty-eight studies involving more than 774 children, 175 parents and 46 families were included. All of the studies were uncontrolled (the specific study designs were not reported).
Psychotropic medication (14 studies).
The results suggested that methylphenidate could improve compliance, on-task behaviours and activity levels in pre-school-age children with ADHD. The effects were observed with both low doses (0.3 mg/kg) and higher doses (1.4 mg/kg). However, although independent observations of child behaviour indicated improvements at low doses, parent and teacher ratings of the child's behaviour were not affected. Only at higher doses were significant changes in parent interactions shown. Side-effects appeared to increase with higher doses of methylphenidate. These included decreased social interaction, loss of appetite and dysphoric mood. Only one study assessed the use of dextroamphetamine. The results of this study showed the children demonstrated improvements in on-task and appropriate play behaviours, but no teacher-reported effects were observed. The results of a study assessing the effectiveness of lithium showed that lithium was associated with increased problem behaviours and significant medication side-effects.
Parent-training interventions (9 studies).
The results of the studies showed that parent-training interventions improved parent-child interactions assessed under analogue conditions. The treatment effects included increases in child compliance, use of appropriate parental commands, knowledge of appropriate parenting techniques, and positive parental statements. In addition, some preliminary evidence suggested that once parenting patterns were established, positive effects in the behaviour of the children could be observed in settings other than the home, and over a long time.
Behaviour management interventions (4 studies).
The results of the studies were inconsistent and inconclusive. One study of cognitive-behavioural training appeared to be developmentally inappropriate for pre-school-age children. A further study of self-instruction training that initially reported positive results could not be replicated.
Multi-component treatment approaches (1 study).
One study examined the effectiveness of a multiple intervention that comprised medication, symbolic modelling and parent training. The results showed that the combination of medication, symbolic modelling and parent training was more effective than medication and symbolic modelling, or medication alone, in improving compliance.