Table 1.
Characteristics of included studies.
| Author (year) | Country | Condition; Age (years) | Mental or cognitive functions | n (ITT); n (PP) | Intervention | Description of Intervention | Frequency | Duration | At-home practice | Comparator | Loneliness scale |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Creswell et al. (2012) | USA | Healthy elderly; 55–85 years (M = 65, SD = 7) | No dementia (according to MMSE score of 27–28) | 40; 34 | MBSR | Group sessions consist of guided mindfulness meditation exercises, mindful yoga and stretching, and group discussions with the intent to foster mindful awareness of one's moment-to-moment experience. A day-long retreat in the sixth or seventh week. | Once weekly 2 h | 8 weeks | Yes−30 min daily practice | Wait-List | UCLA-R |
| Jazaieri et al. (2012) | USA | Adults (M = 32.87, SD = 8.83 [(Intervention); M = 32.88, SD = 7.97 (Control)] | Social anxiety disorder, including some with depression | 56; 30 | MBSR | Group classes, a 1-day meditation retreat, and daily home practice | Once weekly 2.5 h | 3 months | Yes—daily (time NS) | Aerobic exercise | UCLA-8* |
| Dodds et al. (2015) | USA | Women with history of breast cancer; [M = 54.7, SD = 12.1 (Intervention); M = 55.8, SD = 9.7 (Control)] | No obvious condition (according to scales of depression, stress and mental well-being) | 33; 28 | CBCT | Group sessions consist of classes through didactics, class discussion, and guided meditation practice. | Once weekly 2 h | 8 weeks | Yes—at least 30 min practice three times weekly | Wait-List | UCLA-R |
| Mascaro et al. (2018) | USA | Medical students; 22-30 (M = 25, SD = 1.89) | No obvious condition (according to scales of depression) | 59; 32 | CBCT | A sequence of 10 classes included didactic teaching combined with meditations | Once weekly 1.5 h | 10 weeks | Yes−20 min daily | Wait-list | UCLA-R |
| Zhang et al. (2018) | USA | Chinese college students; 17–25 | Elevated loneliness level (claimed by author) | 50; 41 | MBCT | Derived from MBSR and designed for people with a history of recurrent depression to help prevent future recurrences. | Once weekly 2 h | 8 weeks | Yes— (details NS) | Not stated | Indigenous loneliness test |
| On-campus group sessions adapted by substituting the depression-related information with loneliness psychoeducation. | |||||||||||
| Lee et al. (2019) | Korea | Adults with hypertension or/and type-2 diabetes [M = 67.88, SD = 4.95 (Intervention); M = 69.55, SD = 7.22 (Control)] | Not reported | 46; 35 | BEM | A series of yoga-like exercises | Twice weekly of 75 min | 8 weeks | NS | Health education class | Loneliness score as part of mental health test |
| Lindsay et al. (2019) | USA | Adults with stress (M = 32, SD = 14) | Elevated stress level | 153; 93 | 14-lesson, smartphone-based interventions | Mindfulness meditation which involved monitoring present-moment experiences with an orientation of acceptance | Daily 20 min | 2 weeks | Yes−3-10 min daily | Guidance in free reflection, analytic thinking, and problem solving without mindfulness content | UCLA-R |
| Pandya (2019) | India | Elderly (Retired 2–5 years); 62–68 | Probable depression/low mental well-being (according to WEMWBS scale) | 378; 323 | Yoga | Lessons consisted of meditation, asanas (yoga poses) and relaxation. | Once weekly 45 min | 2 years | Yes—once a week (time NS) | No intervention | De Jong Gierveld Loneliness Scale |
BEM, Brain Education-based Meditation; CBCT, Cognitively-Based Compassion Training; ITT, Intention-To-Treat; M, Mean; MBCT, Mindfulness-based cognitive therapy; MBSR, Mindfulness-Based Stress Reduction; MMSE, Mini-Mental State Examination; NS, Not Stated; PP, Per Protocol; SD, Standard Deviation; WEMWS, Warwick-Edinburgh Mental Wellbeing Scale.
*
UCLA-8 Loneliness Scale is a short version of UCLA-R Loneliness Scale.