DISAF 2003

Methods	Dietary Intervention Study for AF (DISAF) RCT, parallel, 2 arms (n‐3 EPA + DHA vs nil), 12 months Summary risk of bias: moderate or high
Participants	People presenting for first treatment of acute/persistent atrial fibrillation or flutter, confirmed by ECG N: intervention 201, control 206 Level of risk for CVD: high (patients with atrial fibrillation) Men: intervention 64.7%, control 63.6% Mean age in years (SD): intervention 67.7 (9.4), control 68.7 (9.5) Age range: unclear Smokers: intervention 10.9%, control 12.1% Hypertension: intervention 48.2%, control 40.8% Medications taken by at least 50% of those in the control group: not reported Medications taken by 20%‐49% of those in the control group: antiarrythmics, antithrombotics Medications taken by some, but less than 20% of the control group: not reported Location: UK Ethnicity: white British
Interventions	Type: dietary advice Comparison: EPA + DHA vs unclear Intervention: dietary assistants gave advice and support to eat 2 to 3 portions of oily fish per week (providing up to 10 g LCn3/ week), plus 2 to 3 portions of fruit and vegetables per day. Dose: 1.4 g/d EPA + DHA. Control: dietary assistants gave advice and support to eat 2 to 3 portions of fruit and vegetables per day. No other health/lifestyle given as part of the trial Compliance: assessed red blood cell fatty acids and found some increases in EPA and DHA in intervention compared to control (no further intake data) Length of intervention: 12 months
Outcomes	Main study outcome: sinus rhythm after 12 months Dropouts: unclear Available outcomes: deaths, AF recurrence Response to contact: yes (data provided)
Notes	Study funding: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was by phone to an independent randomisation office, which used pre‐printed random number tables
Allocation concealment (selection bias)	Low risk	Randomisation was by phone to an independent randomisation office, which used pre‐printed random number tables
Blinding of participants and personnel (performance bias) All outcomes	High risk	Dietary advice was clear, so allocation known by participants
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Unclear
Incomplete outcome data (attrition bias) All outcomes	High risk	Some discrepancies between papers, reasons unclear
Selective reporting (reporting bias)	High risk	ISRCTN16448451 registered 23 January 2004, recruitment from 1 July 1998 to 1 July 2002; some secondary outcomes were not reported
Attention	Low risk	Intervention (advice to eat more oil‐rich fish, fruit and vegetables) and control (advice to eat more fruit and vegetables) groups appeared to be given equivalent time and attention.
Compliance	Low risk	Assessed red blood cell fatty acids and found some increases in EPA and DHA in intervention compared to control
Other bias	High risk	The trial was stopped early