Table 2.
Summary of findings per subjective wellbeing constructs, methadological quality index
| Wellbeing outcome | Number of studies per analysis type | Findings | Methadological quality index range |
|---|---|---|---|
| Depression (23 studies) | Cross-sectional: 16 studies [4, 57–67, 88, 93, 95, 97]. | Fourteen studies found a significant benificial association between friendship quality and depressive symptoms, while two found no association. | 6–15 |
| Longitudinal: 6 studies [83–86, 92, 94, 98]. | Four studies found a significant beneficial relationship between friendship quality and depressive symptoms; two studies found a bidirectional relationship; and one study found no effect. | 12–14 | |
| Case- Control: 1 study [56]. | The study found no significant association between friendship quality and depressive symptoms, neither in adolescents with Asperger’s syndrome nor in typically developed groups. | 7 | |
| Loneliness (10 studies) | Cross-sectional: 8 studies [62, 67–72, 93]. | Seven studies found a significant beneficial association between friendship quality and loneliness, while only one study found no effect. | 8–15 |
| Case-control: 2 studies [55, 56]. | One study found a significant beneficial association between friendship quality and loneliness among typically-developed adolescents but not among adolescents with Asperger’s syndrome, while the other study showed that lonileness score was higher among adolescents with ASD who had poor peer relationships. | 7–8 | |
| Life satisfaction (8 studies) | Cross-sectional: 7 studies [73–77, 89, 91]. | All seven studies found a significant positive association between the quality of friendships and life satisfaction. | 8–10 |
| Longitudinal: 1 study [90]. | The study found a significant positive longitudinal association between friendship quality and life satisfaction. | 13 | |
| Self-esteem (6 studies) | Cross-sectional: 6 studies [66, 67, 78–80, 87, 93]. | All but one study found a significant positive association between the friendship quality and self-esteem. | 7–10 |
| Happiness (5 studies) | Cross-sectional: 4 studies [63; 74; 69, 60]. | All four studies found a significant positive association between friendship quality and happiness. | 8–11 |
| Longitdinal: 1 study [83, 86]. | The study found a significant positive longitudinal association between friendship quality and happiness. | 13 | |
| Subjective wellbeing (5 studies) | Cross-sectional: 4 studies [78, 79, 82, 91] | All four studies found a significant positive association between friendship quality and subjective wellbeing. | 9 |
| Longitudinal: 1 study [96]. | The study found no significant longitudinal association between friendship quality and happiness. | 12 |