In a systematic review and meta-analysis «Pringsheim T, Hirsch L, Gardner D ym. The pharmaco...»1 of the pharmacological management of oppositional behaviour, conduct problems, and aggression in children and adolescents with attention-deficit hyperactivity disorder, oppositional defiant disorder, and conduct disorder the effects of clonidine on oppositional and conduct symptoms was evaluated.
The researchers found 6 RCT-studies of clonidine including 545 children with ADHD. 5 studies did not exclude children with ODD or CD, with rates ranging from 46–100%. The trial sizes ranged from 10–198 subjects, lengths from 6–16 weeks, 2 studies evaluated clonidine added to psychostimulant therapy, 2 studies clonidine monotherapy, 2 both. Methodological quality was rated as II for 4 studies, III for 2 studies. One study used conduct problems as the primary outcome. Among the 4 class II quality studies, 3 were negative regarding oppositional behaviour and conduct problem outcomes. Both class III studies were positive, one was not included in meta-analysis because of lack of data on outcome measures.
Three studies of six provided adequate data on change or end point scores for oppositional behaviour and conduct problems to be included in meta-analyses. The SMD between clonidine and placebo was 0.27 (95% CI 0.04–0.51; I2=0%, Z=2.26, p=0.02) by the fixed effect model.
In the 6 studies the authors found major limitations in study quality, inconsistency in results between studies, no indirectiness, some imprecision of results, possible publication bias, no evidence of dose-response for outcome