Table 1.
Study Characteristics of Randomized Controlled Trials
| Reference | Country | N | Mean Age |
% female |
Population | Intervention | Mode of Delivery |
Total contact hours |
Homework | Instructor Qualifications |
Control type |
Study arms |
HRV measure |
Duration of measurement (mins) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (Carroll & Lustyk, 2018) | USA | 34 | 43.4 | 27 | Substance use disorder | MBRP | Group | 16 | Not reported | Experienced health professional | Passive | 3 | RMSDD | 15 |
| (Crosswell et al., 2017) | USA | 71 | 47 | 100 | Breast cancer survivors | MAP | Group | 12 | 17.5 | Mindfulness teacher with >20 years experience | Passive | 2 | RMSSD | 10 |
| (Delgado et al., 2010) | Spain | 36 | Range 18-24 | 100 | College students high in worry | Mindfulness practices | Group | 10 | Encouraged | Health professional with > 10 years experience | Treatment: CBT techniques | 2 | HF-HRV | 5 |
| (Delgado-Pastor et al., 2015) | Spain | 45 | 21.5 | 100 | College students high in worry | Mindfulness interoceptive training | Group | 6 | Encouraged | Not reported | Passive | 3 | RMSSD | 5 |
| (Dunne et al., 2019) | Ireland | 42 | 41 | 74 | Emergency department personnel | ABT | Group | 16 | 32.5 | Not reported | Passive | 2 | RMSSD | 24 hours |
| (Faucher, Koszycki, Bradwejn, Merali, & Bielajew, 2016) | Canada | 38 | 38 | 38.5 | Social anxiety disorder | MBSR | Group | 27.5 | Prescribed | MBSR instructor with > 20 years experience | Treatment: CBT | 2 | HF-HRV | 30 |
| (Grossman et al., 2017) | Switzerland | 168 | 52.5 | 100 | Fibromyalgia | MBSR | Group | 27 | 42 | MBSR instructors with > 7 years experience | Active and Passive | 3 | RSA | 24 hours |
| (Hunt, Al-Braiki, Dailey, Russell, & Simon, 2018) | USA | 119 | 19.3 | 74 | College students | MBI | Group | 4 | Encouraged | Not reported | Active and Passive | 5 | SDNN | 5 |
| (Kok et al, 2013) | USA | 71 | 37.5 (median) | 66 | University staff | LKM | Group | 6 | Encouraged | Experienced health professional | Passive | 2 | HF-HRV | 2 |
| (Krick & Felfe, 2019) | Germany | 267 | 26.0 | 21.3 | Police officers | MBI | Group | 12 | Prescribed | Experienced instructor | Passive | 2 | RMSSD | 5 |
| (Muthukrishnan, Jain, Kohli, & Batra, 2016) | India | 74 | 22 | 100 | Pregnant women | MBI | Unclear | 10 | 17.5 | Not reported | Passive | 2 | Unclear | unclear |
| (Nyklicek et al., 2013) | Netherlands | 88 | 46.1 | 71 | Stressed community sample | MBSR | Group | 20 | 42 | MBSR instructor with 1 year experience | Passive | 2 | RMSSD | 5 |
| (Oken et al., 2017) | USA | 128 | 59.8 | 80 | Stressed adults age 50+ | MBI | Individual | 7.5 | Encouraged | Experienced instructor | Passive | 2 | SDRR | 5 |
| (Owens et al., 2016) | USA | 19 | 49.4 | 89 | Those with benign heart palpitations | MBSR | Group | 27 | 42 | Not reported | Passive | 2 | RMSSD | 24 hours |
| (Price et al., 2019) | USA | 217 | 35 | 100 | Substance use disorder | MABT | Individual | 12 | Encouraged | Not reported | Active and Passive | 3 | RSA | 5 |
| (Sekar et al., 2019) | India | 30 | 28.5 | 100 | Nurses with perceived stress | Mahamantra Chanting | Individual | 15 | Not clear | Research assistant | Passive | 2 | SDNN | 5 |
| (Wahbeh, Goodrich, Goy, & Oken, 2016) | USA | 114 | 52.1 | 6 | Combat Veterans | Mindful body-scan | Individual | 2 | 14 | Trained research assistant | Passive | 4 | Unclear | 5 |
| (Wolever et al., 2012) | USA | 239 | 42.9 | 77 | Insurance employees | Mindfulness at Work | Group* | 14 | Encouraged | Experienced instructor | Passive | 3 | RR Intervals | 10 |
| (Zimmermann-Schlegel et al., 2018) | Germany | 110 | 58.8 | 22.1 | Type 2 Diabetes Patients | MBSR - modified | Group | 20 | Encouraged | Health professionals | Passive | 2 | RMSSD | 5 |
ABT: Attention Based Training. CEB: Cultivating Emotional Balance. H: High. HRV: Heart Rate Variability. L: Low. LKM: Loving Kindness Meditation. M: Medium. MABT: Mindful Awareness in Body Oriented Therapy. MAP: Mindful Awareness Practices. MBRP: Mindfulness Based Relapse Prevention. MBSR: Mindfulness Based Stress Reduction. MORE: Mindfulness Oriented Recovery Enhancement. MRBWT. Mindfulness and Resource Based Worksite Training. TM Transcendental Meditation.
Group was delivered in either a conventional classroom or virtual classroom allowing for real-time bi-directional communication with no significant differences in effect sizes across modalities. Note. N represents the total study sample size of those randomized to a condition. Mean age and proportion female are calculated based on the total sample size.