Mazereeuw 2016.

Study characteristics
Methods	Randomised controlled parallel‐arm trial, 12 weeks. Subgroup analysis of 21 individuals with MDD (data supplied by authors)
Participants	Participants: 21 participants (Intervention group: 10 participants, mean age 60.7 years (SD 9.8), 6 men, 4 women. Comparator group: 11 participants, mean age 60.1 years (SD 8.0), 7 men, 4 women), recruited from secondary care setting in Canada between August 2010 and February 2014 Comorbidities: Evidence of stable coronary artery disease (history of myocardial infarction, coronary artery bypass graft, percutaneous transluminal coronary angioplasty or at least a 50% stenosis in 1 or more major coronary arteries) in all participants. Possible psychiatric comorbidities Adjunctive therapy: Existing therapy permitted in some participants ("Antidepressant use was permitted if used at a stable dose for at least 3 months before the trial", 2016, p.437) Inclusion criteria: Aged 45 to 80 years with stable coronary artery disease (history of myocardial infarction, coronary artery bypass graft, percutaneous transluminal coronary angioplasty or at least a 50% stenosis in 1 or more major coronary arteries) and has the ability to speak and understand English Exclusion criteria: Excluded patients were those with a significant acute medical illness, a clinically significant cognitive impairment (Standardized Mini‐Mental State Examination [sMMSE] score < 24), a neurological condition, unstable angina (Canadian Cardiovascular Society class 4), ventricular tachycardia or an implantable cardioverter defibrillator, or both, or a high risk of mortality (Killip class > II); who were currently abusing ethanol or other substances; women of childbearing potential, or allergic or hyper‐sensitive to fish; or who have contraindications to soybean/corn oil or a pre‐existing bleeding disorder, history of electroconvulsive therapy, suicidal ideation or a history of suicidal ideation/attempts (determined during SCID‐I at screening/baseline visits); severe depression, defined by Hamilton Depression Rating score > 23; Current or history of psychotic episode or personality disorder
Interventions	Intervention: 1.9 ‐ g n‐3PUFA daily (1.2 g EPA, 0.6 g DHA, with 0.1 g other n‐3PUFA), 3 capsules daily, in an ethyl‐ester form Comparator: 3 g capsules daily of 50/50 soybean/corn oil blend containing < 0.1 ‐ g n‐3PUFA with negligible EPA and DHA Treatment received for 12 weeks.
Outcomes	Primary: HDRS (17‐item), BDI‐II (21‐item) at baseline, 4, 8, 12 weeks, Adverse events Secondary: Quality of life using SF‐36, Trial non‐completion
Notes	Supported by the Ontario Mental Health Foundation, Canadian Institutes of Health Research (MOP 114913). Supplements provided by Ocean Nutrition Canada (Dartmouth, NS). Conflicts of interest: The authors declare no conflicts of interest Compliance: Plasma EPA+DHA concentrations, capsule counts Depressed mood (continuous): Analyses conducted on HDRS‐17 at 12 weeks, as provided by authors. Completers' data only provided Adverse events: 10 events reported in each study arm. Data from completers provided by authors. No data on individuals, so data could not be included in analyses Quality of life: SF‐36 data provided by authors. Completers data only Trial non‐completion: 4 participants dropped out from the intervention group and 2 from the control group. Reasons not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"A block randomisation code was independently computer generated at [outside location]", 2016, p. 437
Allocation concealment (selection bias)	Low risk	"Kits with study medication were consecutively pre‐packaged as per the randomization sequence [..] and were administered in order by study personnel", 2016, p.437
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Participants: "The n‐3 PUFA and placebo capsules were similar in appearance (dark brown) and taste (lemon‐lime flavoring)", 2016, p.437, but no test of blinding. "All study personnel remained blind to treatment allocation until the database was locked.', 2016, p.437
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All study personnel remained blind to treatment allocation until the database was locked.", 2016, p.437
Blinding of outcome assessment (Adverse Events)	Low risk	"All study personnel remained blind to treatment allocation until the database was locked.", 2016, p.437
Incomplete outcome data (attrition bias) All outcomes	High risk	Subgroup data provided for completers only. High withdrawals also
Incomplete outcome data (Adverse Events)	High risk	Subgroup data provided by authors, but for completers only. High withdrawals also
Selective reporting (reporting bias)	High risk	SF‐36 data not reported in text; subgroup analyses are not prespecified in the protocol; additional outcomes reported in the text
Other bias	Unclear risk	Discrepancies between protocol and paper