Vaccarino 2013.

Study characteristics
Methods	Parallel‐group RCT
Participants	Participants were recruited from the community in metropolitan Atlanta through flyers and at health fairs, churches, university campuses, and other community locations, as well as through direct referrals. Recruitment dates not reported. Inclusion criteria: Between the ages of 30 and 65, self‐identified as Black, and met specific criteria for metabolic syndrome. Participants were eligible if they met a modified definition which did not include the standard lipid criteria, but they met 2 out of the following 3 criteria: abdominal obesity (waist circumference > 102 cm in men and > 88 cm in women); BP ≥ 130/≥ 85 mmHg; and fasting glucose ≥ 100 mg/dL. Exclusion criteria: Known CVD or renovascular disease; if they had uncontrolled hypertension (systolic BP > 160 mmHg on two or more occasions or diastolic BP > 105 mmHg); if they were current smokers or had been taking over the counter vitamins (affects endothelial function assessments); if they were pregnant; and if they had documented history of alcohol or drug abuse or other psychiatric or medical diagnoses Number eligible 75; 33 randomised to the intervention group (mean age 51.5, 25% men) and 35 to the comparison group (mean age 52.1, 17.1% men) Medications at baseline: Aspirin therapy at baseline in 21.2% of the intervention group and 14.3% of the comparison group. Statin therapy at baseline in 45.5% of the intervention group and 25.7% of the comparison group. Beta blocker therapy at baseline in 18.2% of the intervention group and 20% of the comparison group. ACE Inhibitor therapy at baseline in 27.3% of the intervention group and 28.6% of the comparison group. Medication change during the trial not reported
Interventions	Intervention (duration 12 months, setting ‐ National Center for Primary Care at Morehouse School of Medicine): Consciously Resting Meditation (CRM) is a sound or mantra‐based meditation. This meditation approach was chosen because of its standardised protocol and its similarity to the TM programme, which has been previously successfully implemented in Black American samples. Both TM and CRM use sounds that have no meaning, but their quieting effects have been known for thousands of years. These sounds, when used properly, settle the mind and body down to a state of restful alertness. As with many TM studies, the CRM programme included 21 sessions over a 1‐year intervention period where participants learned the technique of consciously resting their mind and body. The core instruction involves a 4‐step course over 4 consecutive days (sessions 1 to 4) and a follow‐up programme over 12 months (sessions 5 to 21). Most sessions last 1 to 1.5 hours, and the general format is group meditation plus a lecture/discussion or videotape. In contrast to TM, CRM does not include a private Sanskrit ceremony, which has been a major objection for inner‐city meditation projects. In contrast to TM, CRM can be taught in groups, is less time‐consuming for participants, and is potentially more affordable, making it more accessible and easier to disseminate among minority groups. All sessions were taught by the same experienced teacher. Subjects were instructed to practise CRM twice a day for 20 minutes. Participants were also given the same health education reading materials given to the control group. Comparison (duration 12 months, setting ‐ National Center for Primary Care at Morehouse School of Medicine): Subjects randomised to Health Education (HE) attended the same number, size and frequency of group meetings lead by a professional health educator. The programme included information on prevention of CVD through lifestyle modification and was modelled on educational material disseminated by the American Heart Association. Topics included the value of a healthy diet, exercise, and weight management. The impact of stress was discussed as it relates to weight management and physical exercise. However, to avoid contamination in the experimental design, the HE sessions did not include instructions on stress reduction or relaxation techniques. To match the 20‐minute twice‐a‐day CRM practice, participants were instructed to undertake a 20‐minute twice‐a‐day home practice session applying the recommendations given in this course ‐ diet, exercise, or other lifestyle habits.
Outcomes	Follow‐up at 52 weeks: SBP, DBP, anxiety, depression, psychosocial stress, weight, BMI, HDL cholesterol, glucose
Notes	Country: USA Funding: This study was supported by funding from the National Institutes of Health (NIH)/National Heart, Lung, and Blood Institute U01 HL079156 and U01 HL79214; NIH, National Center for Research Resources (NCRR) Grant M01‐RR00039 for the Emory General Clinical Research Center; NIH/NCRR 5P20RR11104 for the Morehouse Clinical Research Center; and NIH K24HL077506. Declarations of interest: Kofi A. Kondwani, Ph.D., is the founder and CEO of Consciously Resting Meditation (CRM), Inc.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	After completion of baseline assessments, participants were randomised to one of two treatment groups by blocked randomisation with stratification on gender. The random allocation sequence was provided in sealed envelopes by the study statistician (who had no contact with participants) to a staff member not involved in data collection. Patients were randomised in subsequent cohorts of participants, with a minimum of 10 and a maximum of 20 in each randomisation cohort (yielding no more than 10 participants per group who would start the program at any one time), for a total of 5 cohorts.
Allocation concealment (selection bias)	Low risk	The random allocation sequence was provided in sealed envelopes by the study statistician (who had no contact with participants) to a staff member not involved in data collection. Does not specifically say 'opaque' envelopes but judged as low risk.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	The trial was single‐blinded as patients were aware of which intervention they were assigned to (CRM or HE). However, participants were masked to the research hypothesis and both interventions were presented to participants as health‐promoting, which should minimise expectation bias. We have left as unclear risk as it is difficult, if not impossible, to blind participants and personnel to lifestyle interventions.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Investigators and the staff collecting the data were blinded to the treatment status of the participants. The two treatment providers were not involved with participant recruitment, data collection, analysis or interpretation.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Data were analysed following the intention‐to‐treat principle. All outcomes (primary and secondary outcome measures) were analysed as continuous variables using repeated measures mixed‐effects models with treatment group, time point, and other study factors treated as fixed‐effect. The model‐based means are unbiased with unbalanced and missing data, so long as the missing data are non‐informative (missing at random). High attrition at 12 months, so rated as unclear as it is possible data are not missing at random (14/33 (42%) CRM, 16/35 (46%) HE lost to follow‐up at 12 months).
Selective reporting (reporting bias)	Unclear risk	No trial registry or published protocol identified, but report includes all specified outcomes reported in the methods.
Other bias	Unclear risk	Insufficient information to judge