Barrett 2018.

Methods	Study design: randomised controlled trial Location, number of centres: adults from Wisconsin Country: USA Study period: 8‐week training in mindfulness meditation, matched; 8‐week training in moderate‐intensity sustained exercise, or observational control. For the analysis we used the exercise group and the control group. Methods of analysis: "The primary outcome was global severity of ARI illness, defined as area‐under‐the‐time severity‐curve. Daily self‐reports on the Wisconsin Upper Respiratory Symptom Survey (WURSS‐24) assessed symptom severity and quality‐of‐life impact, ARI‐related absenteeism and health care utilization, virus identification, and inflammatory biomarker levels during ARI illness. Secondary outcomes also included several psychosocial domains assessed by validated self‐report instruments at baseline, then 3 or 4 times after intervention. These assessed: general mental and physical health (SF‐12), perceived stress (PSS‐10), sleep quality (PSQI), self‐efficacy (MSES,ESES), mindful awareness (MAAS), positive and negative emotion (PANAS), perceived social support (SPS), and the sense of feeling loved (www.fammed.wisc.edu/feeling‐loved; validation paper under review). Five important personality traits (BFI), the social network (SNI), and co‐morbidities (Seattle Index) were also assessed, but were not expected to be influenced by interventions. The Global Physical Activity Questionnaire (GPAQ) was used to assess self‐reported physical activity in all 3 groups. Blood and nasal wash samples were collected at baseline, 1 and 4 months after the 8‐week interventions, and approximately 24±72 hours into each ARI episode. Biomarkers included: interleukin‐6 (IL‐6), interleukin‐8 (IL‐8), high sensitivity C‐reactive protein (CRP), procalcitonin (PCT), and interferon‐gamma‐induced protein 10 (IP‐10)" Statistical analysis: "The primary efficacy analysis was done using the same zero‐inflated multivariate regression model employed in the first MEPARI trial, which incorporates a logistic sub‐model for people who do not experience ARI illness (zeroes), and a linear sub‐model accounting for variability in the continuous outcome measures (global severity, duration‐of‐illness). Prespecified covariates were: age, gender, body mass index, smoking status, highest level of education achieved, comorbidity, neuroticism, conscientiousness, general physical health, and general mental health. Primary comparisons are between: 1) EX and control, and 2) MBSR and control, with the level of statistical testing set a priori at 0.025 one‐sided for null hypothesis rejection. Secondary analyses are considered statistically significant at alpha <0.01 for evidence‐of‐effect, and at <0.05 for hypothesis‐generation or cautious support of effect based on two‐sided tests. The target sample size of N = 396 for this phase two trial was informed by data from the first MEPARI trial, using alpha = 0.025 and beta = 0.80, and one‐sided testing, for ARI illness primary outcomes"
Participants	Recruitment means: community advertising techniques, screened by telephone interview, and then met twice in person for baseline assessment, written informed consent, and enrolment Target participants: adults aged 30 to 69 years N randomised: 413 adults N completed: 390 adults completed: 146 (exercise), 111 (meditation), 133 (control) Gender M = 100: exercise 30, meditation 33, control 37 F = 313: exercise 107, meditation 105, control 101 Age: exercise (49.1 ± 11.4), meditation (49.2 ± 11.2), control (50.7 ± 12.1) Baseline details: age, gender, smoking, race, BMI, education, income and every questionnaire applied
Interventions	Setting of intervention: interventions were conducted at UW Research Park, a multipurpose outpatient clinic with exercise facilities and space suitable for meditation training. Description of intervention: training in mindfulness‐based stress reduction (MBSR), taught by experienced instructors following standardised MBSR curricula; training in progressive moderate‐intensity exercise (EX); or observational control. Training classes in MBSR or EX were matched in terms of location, class time (2.5 hours per week), homework. The exercise intervention lasted for 20 to 45 minutes a day, with a group of 14 to 16 people. The frequency of the exercise intervention was for at least 5 of the 9 training opportunities. Delivered by: exercise classes were taught by experienced exercise instructors. In addition to the 8 weekly classes, a 5‐hour weekend retreat was held for both EX and MBSR participants. Intervention period: 8 weeks Follow‐up period: screening occurred in the summer, with enrolment and randomisation in August, followed by MBSR or EX training in September and October. Participants were followed through May of the following year using computerised weekly self‐report, periodic in‐person visits, and close surveillance during ARI illness. Weekly self‐reports included daily minutes of MBSR or EX practice.
Outcomes	1. ARI illness burden: severity and duration (number of days), cold severity, symptoms, based on each ARI illness episode, global severity score (area under the curve (AUC)) for all ARI illness days; symptom severity and impact on function and quality of life. 2. Laboratory‐assessed immune parameters included hsCRP neutrophils, IL‐6 (serum and nasal), IL‐8 and IP‐10 3. WURSS‐24, general mental and physical health (SF‐12), perceived stress (PSS‐10), sleep quality (PSQI), self‐efficacy (MSES, ESES), mindful awareness (MAAS), positive and negative emotion (PANAS), perceived social support (SPS), and the sense of feeling loved (www.fammed.wisc.edu/feeling‐loved). 5 important personality traits (BFI), the social network (SNI), and comorbidities (Seattle Index). Global Physical Activity Questionnaire (GPAQ) data collected (in 4 annual cohorts) at baseline, 1 and 4 months after the 8‐week interventions.
Notes	Study funding: "National Center for Complementary and Integrative Health (NCCIH) at the U.S. National Institutes of Health (R01AT006970). During the trial and writing of this paper Bruce Barrett was supported by a mid‐career research and mentoring grant from NCCIH (K24AT006543); Supriya Hayer received support from a research training grant from NCCIH (T32AT006956) directed by Dr. Barrett. MEPARI‐2 received some support from a Clinical and Translational Science Award (CTSA) through the National Center for Advancing Translational Sciences (NCATS), grant UL1TR000427, which also provided research career development support to Elisa Torres (KL2TR000428)"
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"randomization codes generated by an independent statistician using variable block sizes"
Allocation concealment (selection bias)	Low risk	"sealed envelopes"
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants could not be blinded due to the characteristics of exercise and meditation.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"investigators remained masked to group assignment until after the last participant exited"
Incomplete outcome data (attrition bias) All outcomes	Low risk	There was low loss to follow‐up, and intention‐to‐treat analysis was performed.
Selective reporting (reporting bias)	Low risk	All the outcomes (primary and secondary) described in the protocol were reported.
Other bias	Low risk	The study seems to be free of other sources of bias.