Ornish 1990.

Methods	Study design: Multicentre RCT (2 sites) Country: US Dates patients recruited: NR Maximum follow up: 5 years
Participants	Inclusion criteria: Age 35‐75 years, male or female; residence in the greater San Francisco area; one, two, or three vessel CAD (defined as any measurable coronary atherosclerosis in a non‐dilated or non‐bypassed coronary artery); LVEF > 25% Exclusion criteria: Other life‐threatening illnesses; MI during the preceding 6 weeks, history of receiving streptokinase or alteplase; currently receiving lipid‐lowering drugs; scheduled to receive CABG. N Randomised: total: 48; intervention: 28; comparator: 20 Diagnosis (% of pts): moderate to severe CAD: 100% Age (mean ±SD): Intervention: 56.1 ± 7.5; Comparator: 59.8 ± 9.1 Percentage male: Intervention: 95%; Comparator: 79% Ethnicity: NR
Interventions	Intervention: The intervention began with a week‐long residential retreat at a hotel to teach the lifestyle intervention to the experimental‐group patients. Patients then attended regular group support meetings (4h twice a week). Patients were individually prescribed exercise levels (typically walking) according to their baseline treadmill test results. Patients were asked to exercise for a minimum of 3 h per week and to spend a minimum of 30 min per session exercising within their target heart rates. Components: Setting: centre. Aerobic exercise: Modality: typically walking. Length of session: minimum of 30 min. Frequency: up to 6 times a week. Intensity: heart rate of 50‐80%. Resistance training included? No. Total duration: 1 year. Co‐interventions: stress management, low fat vegetarian diet, group psychosocial support. Comparator: usual care. Co‐interventions: none described.
Outcomes	CHD mortality, non‐fatal MI, revascularisation. Assessment at baseline and after 1 year and 5 years.
Source of funding	National Heart, Lung, and Blood Institute of the National Institutes of Health, the Department of Health Services of the State of California, Gerald D. Hines Interests, Houston Endowment Inc, the Henry J. Kaiser Family Foundation. the John E. Fetzer Institute, Continental Airlines, the Enron Foundation, the Nathan Cummings Foundation, the Pritzker Foundation, the First Boston Corporation, Quaker Oats Co., Texas Commerce Bank, Corrine and David Gould, Pacific Presbyterian Medical Center Foundation, General Growth Companies, Arthur Andersen and Co.
Conflicts of interest	NR
Notes	Intervention group had 91% reduction in reported frequency of angina after 1 year and 72% after 5 years, comparator group had 186% increase in reported frequency of angina after 1 year and 36% decrease after 5 years. Intervention group had 7.9% relative improvement in coronary artery diameter at 5 years, comparator group had 27.7% relative worsening at 5 years.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly assigned"
Allocation concealment (selection bias)	Unclear risk	Not reported.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"Investigators carrying out out all medical tests remained unaware of both patient group assignment and the order of the tests".
Incomplete outcome data (attrition bias) All outcomes	High risk	45/93 (48%) of randomised patients did not participate, no description of withdrawals or dropouts.
Selective reporting (reporting bias)	High risk	Outcomes are only presented for 1 year, although blood tests were also taken at 6 months.
Groups balanced at baseline	Low risk	"The experimental and control groups did not differ significantly in disease severity at baseline".
Intention‐to‐treat analysis conducted	High risk	No.
Groups received same treatment (apart from the intervention)	High risk	"Patients were assigned to an experimental group or to a usual‐care control group. Experimental‐group patients were prescribed a lifestyle programme that included a low‐fat vegetarian diet, moderate aerobic exercise, stress management training, stopping smoking, and group support. Control‐group patients were not asked to make lifestyle changes, although they were free to do so.”