NDHS Faribault 1968.

Methods	RCT
Participants	Men living in a mental health institute (USA) CVD risk: low Control: randomised 57, analysed 52 Interventions B, C, E combined: randomised 167, analysed 143 Mean years in trial: control 1.0, Interventions 0.9 % male: 100 Age: unclear (all 45‐54)
Interventions	Modified fat vs. usual diet Control aims: total fat 40%E, SFA 16‐18%E, dietary chol 650‐750mg/d, P/S 0.4 Intervention aims: B (C, E) total fat 30%E (40%E, 40%E), SFA <9%E (<9%E, not stated), dietary chol 350‐450mg/d (350‐450mg/d, not stated), PUFA 15%E (18‐20%E, not stated), P/S 1.5 (2.0, 4.4) Control methods: whole diet provided Intervention methods: whole diet provided Total fat intake (at 28 & 44 weeks combined): B (C, E) mod fat 29.2 (38.5, 37.1) (sds unclear)%E, cont 39.4 (sd unclear)%E Saturated fat intake (at 28 & 44 weeks combined): B (C, E) mod fat 6.6 (7.4, 4.9) (sds unclear)%E, cont 15.6 (sd unclear)%E Style: diet provided Setting: residential institution
Outcomes	Stated trial outcomes: lipid levels and dietary assessment Data available on total mortality? yes Cardiovascular mortality? no Events available for combined cardiovascular events: none Secondary outcomes: no cancer deaths or diagnoses occurred Tertiary outcomes: total cholesterol
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Stratified randomisation by the statistical centre
Allocation concealment (selection bias)	Low risk
Blinding (performance bias and detection bias) All outcomes	Low risk	Double blind, facilitated by provision of the whole diet
Incomplete outcome data (attrition bias) All outcomes	Low risk	Institution so able to follow up all participants through study.
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?	Low risk	Whole diet provided for both groups. See Control and Intervention Methods in Interventions section of the Table of Characteristics of Included Studies
Free of dietary differences other than fat?	Low risk	See Control and Intervention Aims in Interventions section of the Table of Characteristics of Included Studies