Table 4.
Study Description and Relevant Findings: Intervention Studies
| Author (year), country | Sample | Total N (% male participants) | Age range at baseline, y | Mean age (SD) | Loneliness measure | Mental health measures | Intervention | Comparison condition | Main findings |
|---|---|---|---|---|---|---|---|---|---|
| King et al. (2018),81 USA |
Experienced bullying/Victimization, recruited via paediatric medical emergency services | 218 (33. 5) | 12–15 | 13. 50 (1. 1) | Revised UCLA Loneliness Scale | Reynolds Adolescent Depression Scale−2 short; Columbia Suicide Severity Rating Scale | LET’S CONNECT (LC) mentorship program (strengths-based approach) Mentorship lasted an average of 120.32 days (SD = 69.69), 4−6 h/mo | No treatment | At 6 months, loneliness decreased more in LC intervention group than in control group (p < . 01) ES = 0.4 |
| Larsen et al. (2019), 82 Norway |
School students | 2,254 (NS; estimate 53). | 15–19 | 16. 82 (NS) | Loneliness Scale (modified) | Symptom Checklist | Dream School Program; aimed to change psychosocial environment of classroom, including through peer mentors and a staff mental health support team. Two classes over two semesters | Education as usual. | No significant effects on mental health or loneliness for either intervention group |
Note: ES = effect size; NS = not specified.