Barragán 2017.

Study characteristics
Methods	A 12‐month randomised, unblinded parallel‐trial with 3 arms: omega 3/6 LA‐MPH omega 3/6 and LA‐MPH
Participants	Number of participants screened: 107 Number of participants included: 60 for the 2 relevant groups (90 in all (60 boys, 30 girls)) Number of participants followed‐up: 49 for relevant groups (69 in all) Number of withdrawals: 11 from omega group and combined group (10 more in MPH group) Diagnosis of ADHD: DSM‐IV‐TR (51 (57%) combined type, 7 (8%) hyperactive‐impulsive type and 32 (36%) inattentive type) Age: mean 8.27 years (SD 1.74; range 6‐12) IQ: not stated MPH‐naive: 100% Ethnicity: not stated Country: Mexico Setting: outpatient Comorbidity: some were exclusion criteria Comedication: medication for chronic conditions specified as exclusion criteria Additional sociodemographics: none Inclusion criteria 6‐12 years Newly diagnosed with ADHD of any subtype Exclusion criteria Neurologic disorders (epilepsy, brain damage, mental disability) Autism or pervasive developmental disorders Known hypersensitivity to components of omega‐3/6 Previous pharmacological treatment for ADHD Ongoing chronic conditions (e.g. asthma) Medication for chronic conditions Children not receiving school assistance
Interventions	30 participants were randomly assigned to: 3 different groups, omega 3/6 twice daily, MPH or a combination Mean medication dosage: combined group: baseline: 0.49 mg/kg, month 1: 0.79 mg/kg, month 3: 0.8 mg/kg Administration schedule: not stated Duration of each medication condition: 12 months Washout before trial initiation: not stated Titration period: during the first 4 weeks Treatment compliance: not stated
Outcomes	ADHD symptoms Spanish version of the ADHD‐RS, parent‐rated at baseline, 1 month, 3 months, 6 months, and 12 months Non‐serious AEs Evaluated at each clinic appointment
Notes	Sample calculation: no Ethics approval: “[…] the trial was approved by the local ethical review board.” Comments from trial authors Strengths of the present trial: the 3‐arm design the 12‐month duration the high retention rate Limitations of the trial: a possible lack of statistical power as a result of the exploratory nature of the trial no formal sample‐size calculation resulting in a small sample size, especially for a non‐inferiority trial the non‐blinded trial design the lack of a placebo arm the high baseline disease severity Key conclusion of trial authors In conclusion, the tested combination of omega‐3/6 fatty acids was slightly less effective than MPH in this unblinded RCT While no statistical superiority of the combination of MPH and omega‐3/6 fatty acids compared with MPH was found in terms of efficacy, the combination appeared to have some benefits over MPH monotherapy in terms of MPH dosing and tolerability, which may in turn lead to improvements in compliance. Exclusion of MPH non‐responders/children who have previously experienced AEs while taking MPH: no Any withdrawals due to AEs: yes, 2 (6 more in the MPH group) Funding source: Vifor Pharma Email correspondence with trial authors:contacted through personal email in August and October 2021, for information regarding participant data, but no answer received
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomised (unblinded) by means of an aleatorised table to receive MPH, omega‐3/6, or combination therapy with MPH + omega‐3/6.
Allocation concealment (selection bias)	High risk	None
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not blinded
Incomplete outcome data (attrition bias) All outcomes	High risk	The main analyses were ITT analyses with LOCF for patients who dropped out Selection bias (e.g. titration after randomisation → exclusion of MPH non‐responders or placebo responders): yes, withdrawals due to "no efficacy"
Selective reporting (reporting bias)	Unclear risk	No trial protocol available