Prevalence estimates of attention deficit hyperactivity disorder (ADHD) vary according to the diagnostic criteria used and the population sampled. DSM-IV prevalence estimates among school children in the US are 3-5%, but other estimates vary from 1.7% to 16.0%. No objective test exists to confirm the diagnosis of ADHD, which remains a clinical diagnosis. Other conditions frequently co-exist with ADHD.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of pharmacological treatments for ADHD in children and adolescents? What are the effects of psychological treatments for ADHD in children and adolescents? What are the effects of combination treatments for ADHD in children and adolescents? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
We found 34 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
In this systematic review we present information relating to the effectiveness and safety of the following interventions: atomoxetine, bupropion, clonidine, dexamfetamine sulphate, homeopathy, methylphenidate, modafinil, omega 3-polyunsaturated fatty acids, and psychological/behavioural treatment (either alone or in combination with a drug treatment).
Core symptoms of ADHD are inattention, hyperactivity, and impulsiveness, although other conditions frequently coexist with ADHD, including developmental disorders (especially motor, language, social communication, and specific learning disabilities) and psychiatric disorders (especially oppositional defiant and conduct disorder, anxiety, and depressive disorders).
Symptoms must be present for at least 6 months, are generally observed in children before the age of 7 years, and cause clinically important impairment in social, academic, or occupational functioning which must be evident in more than one setting.Formal diagnostic criteria are most applicable to boys aged 6-12 years, and most research data relate to this group. Preschool children, adolescents, and females may present less-typical features, but similar levels of impairment. Prevalence estimates among school children range from 3% to 5%.
Methylphenidate improves core symptoms and school performance in children with ADHD when used alone.
Dexamfetamine and atomoxetine may also reduce symptoms of ADHD.
We don't know how effective any treatment for ADHD is in the long term; people with ADHD may require treatment for many years.
CAUTION: Atomoxetine may cause rare but serious liver injury.
Clonidine and modafinil may improve symptoms of ADHD compared with placebo, but are associated with an increased risk of adverse effects compared with methylphenidate, dexamfetamine, and atomoxetine.
We don't know whether homeopathy,
bupropion, or polyunsaturated fatty acids are beneficial in the treatment of symptoms of ADHD.
We don't know how effective psychological/behavioural treatments alone are compared with each other or with pharmacological treatments, as we found few high-quality studies.
The combination of methylphenidate plus psychological treatment may enhance effectiveness of methylphenidate alone or behavioural treatment alone, but we don't know whether dexamfetamine plus psychological treatment is effective in treatment of ADHD compared with either intervention alone. Long-term outcome for both drug treatment alone and combination treatments is uncertain.We don't know whether parent training in conjunction with teacher involvement is more effective than parent training alone.