ADHD medications, such as methylphenidate and amphetamines, can effectively treat children’s symptoms; however, they are ineffective for some children and can cause a range of side effects (see a recent blog here).
Non-pharmacological interventions offer an alternative and complementary approach for treating ADHD. NICE guidelines currently recommend psychoeducation and support, CBT, changes to diet, exercise and parent-training; yet many other treatments have been investigated (NICE, 2018).
This systematic review evaluated the evidence for non-pharmacological interventions in children and adolescents published between 2009 and 2016 (Goode et al, 2018).
The authors followed standard protocols for conducting systematic reviews recommended by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the US-based Agency for Healthcare Research Quality (AHRQ). They searched for original research studies in the PubMed, Embase, PsycINFO, and Cochrane databases for the period January 2009 – November 2016.
Several inclusion criteria were specified:
- Children and adolescents with a diagnosis of ADHD from 0 to 17 years of age receiving a non-pharmacological treatment for ADHD
- A measure of change on standardised ADHD rating scales or progress toward patient-identified goals
- Comparison to another non-pharmacological treatment, approved pharmacological treatment, or a control group receiving placebo, usual care, or waitlist
- Minimum sample size of 50 to exclude pilots and possible low quality studies
Two authors screened each abstract, title, and full text article, and extracted the data. Disagreements were resolved through discussion or a third expert. The quality of studies and potential for bias were assessed on the Cochrane risk-of-bias tool for randomised studies and the Newcastle-Ottawa scale for observational studies. Studies were rated as good, fair, or low quality, and were specific to each outcome measured. The Strength of Evidence was also assessed as insufficient, low, moderate, or high according to the AHRQ guide, which addresses limitations, consistency, directness, precision, and reporting bias.
Random effects meta-analysis was conducted for comparisons with at least three studies, which was only possible for the effect of omega-3/6 supplementation compared to placebo on teacher (n=3) and parent ratings (n=4) of ADHD symptoms.
The authors identified 54 studies. Most were randomised controlled trials with good or fair quality. However, the follow-ups were typically short, controls varied, and the outcomes assessed were different across studies. The outcomes on standardised ADHD symptom rating scales are summarised below (see Kemper et al., 2018, for the full review).
One good quality randomised controlled trial (RCT, N = 102) reported improvement in parent-rated ADHD symptoms compared to attention skills training and another (N = 104) reported improvement in parent- and teacher-rated ADHD symptoms compared to cognitive training or a waitlist control. A third good quality RCT (N = 90) reported no significant changes in symptom scores compared to treatment as usual. Finally, one poor quality RCT (N = 91) reported no differences in parent-reported symptoms for neurofeedback with methylphenidate and compared to methylphenidate alone. Neurofeedback was judged to have insufficient evidence.
Cognitive training did not significantly improve symptom scores compared to placebo training in three good quality RCTs (N = 225) or compared to an alternative cognitive and compensatory training in one fair quality RCT (N = 105). Cogmed working memory training improved symptom scores compared to a waitlist control in one fair quality RCT (N = 52) but not in one good quality RCT (N = 75). Cognitive training was judged to have low strength of evidence.
One good quality RCT (N = 119) found that CBT significantly improved self- and parent-reported ADHD symptoms compared to usual care. One fair quality study (N = 159) found that CBT with planning skills training significantly improved symptom scores at three and twelve months compared to typical CBT. CBT was judged to have low strength of evidence.
Two good quality RCTs (N = 170) found that psychoeducation for parents and families significantly improved symptom scores at three months compared to counselling. A good (N = 120) and fair quality RCT (N = 120) found that behavioural parent training alone did not improve ADHD symptoms compared to a passive control group. There was, however, evidence of improved symptom scores in behavioural interventions that incorporated parent training with child or teacher training in two good (N = 191) and one fair quality RCT (N = 97) compared to treatment as usual. A fair quality RCT (N = 57) found that behavioural parent, teacher, and child training did not improve symptoms compared to pharmacological treatment; however, the reviewers reported that it was more effective. Lastly, a good quality RCT (N = 244) found that behavioural parent training and sleep hygiene did not improve symptoms immediately but did improve parent-reported symptoms after three months compared to waitlist. Child/parent training and behavioural interventions were judged to have moderate strength of evidence.
A meta-analysis of four good quality RCTs (N = 411) showed that omega-3/6 supplements had a small (d = 0.32) but non-significant effect on parent-rated symptom scores compared to placebo. The corresponding meta-analysis on teacher ratings showed no effect of omega-3/6 supplements in two good and one fair quality RCTs (N = 289). Two other studies showed no effect on parent or teacher ratings compared to placebo or usual care. Omega-3/6 supplements were judged to have moderate strength of evidence.
Dietary and herbal interventions
One good quality RCT (N = 100) found that a restricted elimination diet improved parent- and teacher-reported symptom scores compared to a nonrestricted diet. A fair quality RCT (N = 52) found that zinc supplements twice daily was no better than zinc supplements once daily or placebo. A good quality RCT (N = 72) found no differences in symptom scores after children received ningdong granule or methylphenidate. A good quality RCT (N = 50) found that methylphenidate improved parent- and teacher-rated symptom scores more than ginkgo biloba. A good quality RCT (N = 86) found that memomet syrup significantly improved symptom scores compared to placebo. Finally, a fair quality RCT (N = 54) found no difference in children receiving vitamin D and methylphenidate or placebo and methylphenidate. Dietary and herbal interventions were judged to have low strength of evidence.
Summary: strength of evidence
- Omega-3/6, child/parent training and behavioural interventions were judged to have moderate strength of evidence
- CBT, cognitive training, and herbal/dietary interventions were judged to have low strength of evidence
- Neurofeedback was judged to have insufficient evidence
The authors concluded that the review provided little new evidence that could guide current non-pharmacological treatment for ADHD. The strength of evidence was generally low, follow-up durations were limited, and patients were often not seen in primary care settings.
Strengths and limitations
This was a broad systematic review that followed standard protocols, compiled a multitude of results, and considered treatment effects in relation to the type of control group used.
Considerable heterogeneity in treatments and outcomes limited the ability to run meta-analyses and to form firm conclusions. This was particularly true for behavioural child/parent training interventions and herbal/dietary approaches, which were very broadly categorised and could have been considered on a study-by-study basis. There was little evidence for behavioural parent training alone, but psychoeducation and combined approaches, with child and/or teacher training were more effective. Furthermore, restricting the timeframe and sample size of eligible studies omitted data that could have contributed to the review or meta-analyses.
The reviewers did not report on the blinding of outcome assessors. This is important because ADHD symptoms were mostly evaluated by parent-ratings, which are often not blinded and are biased in favour of non-pharmacological interventions for ADHD (Cortese et al., 2015; 2016).
Although placebo-controlled studies were included, many studies used either a waitlist or usual care control group, which may not have sufficiently controlled for expectancy. Furthermore, interpretations of null effects in comparison to another non-pharmacological or pharmacological treatment are limited because both interventions could have been effective or ineffective.
Implications for practice
This review does not suggest changes to current best practice for treating children with ADHD; however, at the individual study level it does highlight some promising findings that warrant further investigation.
Goode AP, Coeytaux RR, Maslow GR, et al. (2018) Nonpharmacologic Treatments for Attention-Deficit/Hyperactivity Disorder: A Systematic Review. Pediatrics. 2018;141(6):e20180094 https://doi.org/10.1542/peds.2018-0094
NICE (2018) Attention Deficit Hyperactivity Disorder: Diagnosis and Management of ADHD in Children, Young People and Adults. NICE Guideline 87. https://www.nice.org.uk/guidance/NG87. Accessed January 14, 2019.
Kemper, A. R. et al. (2018). Attention Deficit Hyperactivity Disorder: Diagnosis and treatment in children and adolescents. Rockville, MD: Agency for Healthcare Research and Quality. https://doi.org/10.23970/AHRQEPCCER203
Cortese, S., Ferrin, M., Brandeis, D., Buitelaar, J., Daley, D., Dittmann, R. W., … & Zuddas, A. (2015). Cognitive training for attention-deficit/hyperactivity disorder: meta-analysis of clinical and neuropsychological outcomes from randomized controlled trials. Journal of the American Academy of Child & Adolescent Psychiatry, 54(3), 164-174. https://doi.org/10.1016/j.jaac.2014.12.010
Cortese, Samuele, Maite Ferrin, Daniel Brandeis, Martin Holtmann, Pascal Aggensteiner, David Daley, Paramala Santosh et al. “Neurofeedback for attention-deficit/hyperactivity disorder: meta-analysis of clinical and neuropsychological outcomes from randomized controlled trials.” Journal of the American Academy of Child & Adolescent Psychiatry 55, no. 6 (2016): 444-455. https://doi.org/10.1016/j.jaac.2016.03.007