Stimulant medication for children with Attention Deficit Hyperactivity Disorder (ADHD)
The findings of a systematic review of the effects of a commonly prescribed stimulant medication, methylphenidate, which you may know better as Ritalin, for children with ADHD received attention from the media with coverage that can best be described as ‘the good, the bad, and the ugly’. The review reported improvements in teacher rated ADHD symptoms and parent reported quality of life following medication use. Medication use was not associated with an increase in serious life threatening harmful events but was associated with an increased risk of less serious side effects such as sleep problems and reduced appetite. The reviewers used the ‘gold-standard’ Cochrane review method and provided a plain language summary of the findings. With such well-defined findings, why did the media coverage vary so much?
The review itself
The researchers emphasised throughout the review that the 185 trials they reviewed were assessed as ‘at high risk of bias’. This led them to conclude that the findings they report concerning teacher reported ADHD symptom improvements and parent rated quality of life improvements were based on ‘low quality evidence’. Blogs picked up on this aspect of the reporting, with NHS Choices stating ‘experts call for more research into ADHD drug Ritalin’. The media also emphasised the caution raised by the researchers. One headline read ‘Experts call for caution over Ritalin’ and another ‘ADHD drug Ritalin should be prescribed with caution because scientists STILL can’t say whether it’s safe after 50 years of use’. It’s not surprising that these interpretations would be made, given the researchers clear conclusions about the trials reviewed being ‘small and of low quality’.
The reference to low quality evidence and the researcher’s basis for this is where I find the interpretation tricky. I am an author of one of the RCTs reviewed in this paper. Our review was described by the researchers as one of 13 trials that randomised participants but also stated that we (and the other 12 papers) didn’t make it clear how many participants were followed up. This is untrue, at least for our paper. The number of participants followed up in our study is clearly described in the CONSORT diagram provided with the paper and referred to within the results section. Another trial reviewed, which was conducted by a collaborator of mine Professor David Coghill, was described as having insufficient information for assessment of whether the method used to handle missing data was likely to bias the estimate of effect. This information was in fact presented at three points within the paper. It is therefore difficult for me to be convinced of the conclusion that existing trial data is all ‘at high risk of bias’, when the two studies I know of personally have been miscoded and misrepresented. This is a shame because the review clearly reports significant parent and teacher related improvements with medication in children with ADHD, but for which the researchers have low confidence in, because of what they interpret as low quality evidence.
The good, the bad, and the ugly
First of all let us look at the good reporting. The BBC reporting of the review stayed close to the wording of the review summary. They referred to the higher risk of side effects with medication reported in the review (sleeping problems and reduced appetite) but also concluded that ‘the international researchers said this did not mean that the drugs are not useful – the Cochrane findings suggest they do help children concentrate at school – but any benefits must be closely weighed against the risk of side effects’. The BBC also drew on the opinions of two independent experts – Daniel Hawcutt from the British Pharmacological Society and Dr Tony Lloyd from the ADHD Foundation, a practice we have continually emphasised at Research the Headlines.
Now to the bad. Other newspapers ran with inaccurate headlines that suggested that stimulant medication did not improve ADHD. Examples included British coverage ‘Ritalin may not help ADHD’ and the Australian headline ‘Ritalin may not help children with ADHD’. Neither of these newspapers went on to explain these headlines specifically and clearly ignored the actual findings of the review to focus on the researcher’s appraisal of ‘low quality evidence’. However – whether low quality or not – the evidence does show that Ritalin can help teacher reported ADHD symptoms and parent reported quality of life. These headlines are simply not accurate. It is very concerning to see headlines like this because many people ‘stop at the headline’ and it could well be that a parent decides to discontinue treatment as a result of reading headlines like this rather than making these decisions with their doctor, paediatrician or psychiatrist.
And now to the ugly. The Daily Mail ran with a headline ‘we will live to regret trying to cure ‘naughty’ children with drugs’. So before we even move beyond the headline we are talking about ‘naughty’ children rather than the samples reviewed who had a diagnosed disorder. The article goes on to say that ‘there’s a broader worry about the ADHD label itself. Parents are coming into schools telling mystified teachers that their child has just been diagnosed and has to take a mind-altering substance every day. Yet the teachers have not noticed any behaviour problems in school — which suggests it’s something that only happens at home’. This is a completely ignorant description of ADHD – the diagnosis requires confirmation of symptoms across settings which invariably for a child will be parent and teacher verification of both symptoms and impairment. The article also makes out that the diagnosis is given for normal everyday distraction and inattention – ‘it’s too easy to jump on the ADHD bandwagon and use it to justify being easily distracted or bored’. At the heart of the diagnosis – and any diagnosis – is the concept of functional impairment. Children receive the diagnosis because their symptoms cause them to have significant difficulty at home, with school work and in peer relationships. As one of the independent experts (Tony Lloyd, ADHD Foundation) interviewed by the BBC commented ‘ADHD is still under-recognised and under-treated in the UK’. It is a misconception that a child would receive a diagnosis of ADHD for showing everyday boredom.
This review reports significant positive effects of treatment with methylphenidate (Ritalin) on ADHD symptoms and quality of life. Side effects are a risk factor of medication use (sleeping difficulties and reduced appetite) and have to be weighed up alongside potential benefits. In context, this applies to all prescriptions of psychiatric medicine. The medication is assessed as not having life threatening harmful effects. Bottom line, parents should make any decisions about their child’s medication use with advice from the GP, paediatrician or psychiatrist involved in their child’s health care.