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Table 1 Double blind placebo-controlled trials of omega-3 fatty acids upon attention and hyperactivity in disorders diagnosed in childhood.

From: Omega-3 fatty acids as treatments for mental illness: which disorder and which fatty acid?

Ref Jadad score Disorder Meds Age Gen Omega-3 fatty acid Prep type Duration N Outcomemeasure Average baseline score Δ Statistical significance vs. placebo
25 4 ADHD 100% 9 22% 345 mg/day EPA Crude Mixture 4 months 54 CBC-Attention 66 +0.4 No
28 5 ADHD 15% 9 20% 100 mg/day EPA
512 mg/day DHA
Crude mixture in food 2 months 40 #DSM-Attention 9.5 -1 No
           #DSM-Hyperactivity 2 0 No
29 5 LD NS 10 20% 186 mg/day EPA
480 mg/day DHA2
Crude mixture 12 weeks 29 CPRS DSM-Attention 63 -4.6 Yes
           CPRS DSM-Hyperactivity 67 -1.0 No
30 3 'ADHD-like' 79% 10 12% 80 mg/day EPA
480 mg/day DHA1
Crude mixture 4 months 47 PDBDS-Attention 22 +0.2 No
           PDBDS-Hyperactivity 22 -0.6 No
32 5 DCD 0% 9 33% 558 mg/day EPA
174 mg/day DHA3
Crude mixture 12 weeks 117 CPRS DSM-Attention 65 -3.5 Yes4
           CPRS DSM-Hyperactivity 61 -3.8 Yes4
           Spelling age (months) 94 +5.4 Yes
           Reading age (months) 97 +6.2 Yes
34 4 Autism 0% 10 18% 840 mg/day EPA
700 mg/day DHA
Crude mixture 6 weeks 13 ABC-Hyperactivity 29 -7.0 No
  1. ADHD, LD and DCD are Attention Deficit Hyperactivity Disorder, Learning Difficulties and Developmental Coordination Disorder respectively. Δ refers to the difference between the change from baseline values for placebo and treatment groups (change from baseline symptom scores for the omega-3 fatty acid group minus change from baseline scores for the placebo group). Trial quality was assessed using Jadad design quality scores which can range from 0 to 5 with 5 being best. Outcome measures are CBC – Attention: Child Behaviour Checklist – Attention Subscale; PDBDS – Attention/Hyperactivity: Attention or Hyperactivity Subscale of Parents Disruptive Behaviour Disorder Scale, #DSM – Attention/Hyperactivity: Number of DSM ADHD Attention or Hyperactivity symptoms present, CPRS DSM – Attention/Hyperactivity: DSM Attention/Hyperactivity Subscale of Conner's Parent Rating Scale Clinical Global Impression, ABC-hyperactivity: Aberrant Behaviours Checklist [34] For reading and spelling age a higher age is better hence positive Δ indicates improvement over placebo, for all other scales 0 is best hence negative Δ indicates improvement over placebo. The average baseline score is the average of the omega-3 and placebo group scores at the start of the trial. Age refers to the average age in years of the active and placebo groups. Gen (gender) refers to the % of female participants in the trial. Meds refers to the percentage of trial participants who were in receipt of conventional medications for attentional deficit or hyperactivity. Prep. type describes whether a crude oil mixture or a purified fatty acid was used. Notes: 1–3 Formulation also delivered omega-6 fatty acids: 1 40 mg/day arachidonic acid and 96 mg/day gamma linoleic acid, 2 96 mg/day gamma linoleic acid, 864 mg/day linoleic acid and 42 mg/day arachidonic acid, 3 60 mg/day linoleic acid. 4 According to the report it is unclear as to whether statistical significance was calculated using raw scores rather than transformed t-scores. Using the data in the paper the statistical significance of the t-score comparison cannot be calculated.