Methods	RCT
Participants	Middle-aged siblings of people with early CHD, with at least one CVD risk factor (USA) CVD risk: moderate Control: randomised 132, analysed 118 Intervention: randomised 135, analysed 117 Mean years in trial: 1.9 % male: control 49%, intervention 55% Age: control mean 45.7 (sd 7), intervention 46.2 (sd 7)
Interventions	Reduced fat intake vs. usual diet Control: physician management (physicians informed on risk factor management) Intervention: nurse management, aim total fat 40g/d or less Control methods: physician management with risk factor management at 0, 1 and 2 years Intervention methods: nurse management, appointments 6-8 weekly for 2 years Total fat intake (at 2 years): low fat 34.1 (sd unclear), cont 38.0 (sd unclear)%E Saturated fat intake (at 2 years): low fat 11.5 (sd unclear), cont 14.4 (sd unclear)%E Style: diet advice Setting: community
Outcomes	Stated trial outcomes: dietary intake Data available on total mortality? yes, no deaths Cardiovascular mortality? yes, no deaths Events available for combined cardiovascular events: total MI, stroke, unstable angina, PVD and PTCA Secondary outcomes: cancer diagnoses (no events), cancer deaths (none), stroke, total and non-fatal MI Tertiary outcomes: BMI, HDL and LDL cholesterol, TG
Notes
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomly assigned via computerised schema after all eligible siblings from a family had been screened
Allocation concealment (selection bias)	Unclear risk	Randomisation method not clearly described
Blinding (performance bias and detection bias) All outcomes	High risk	Participants and trialists clear about their allocation
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear, deaths, cancer and CV events are drop-outs, trialists asked for data - unclear if any data missing
Selective reporting (reporting bias)	Low risk	Not relevant for primary and secondary outcomes as all trialists asked for data
Other bias	Low risk
Free of systematic difference in care?	High risk	Differences in frequency of follow up, but unclear what differences in care occurred between the physician and nurse-led care. See Control and Intervention Methods in Interventions section of the Table of Characteristics of Included Studies
Free of dietary differences other than fat?	Unclear risk	See Control and Intervention Aims in Interventions section of the Table of Characteristics of Included Studies