TABLE 2.
Results of meta‐analyses comparing psychological outcomes of outdoor physical activity in natural and urban environments
| Outcome | No. of participants (studies) | Statistical method | Effect estimate [95% CI] | I 2 | χ 2 (df) |
|---|---|---|---|---|---|
| Anxiety | 720 (7) | Std. mean difference (IV, random, 95% CI) | −6.59 [−10.04, −3.13]* | 91% | 66.98 (df = 6)** |
| Depression | 697 (5) | Mean difference (IV, random, 95% CI) | −0.34 [−0.62, −0.05]* | 74% | 15.12 (df = 4)** |
| Anger/hostility | 697 (5) | Mean difference (IV, random, 95% CI) | −0.57 [−0.79, −0.35]* | 30% | 5.71 (df = 4) |
| Fatigue | 697 (5) | Mean difference (IV, random, 95% CI) | −1.98 [−2.77, −1.19]* | 79% | 19.18 (df = 4)** |
| Vigour | 697 (5) | Mean difference (IV, random, 95% CI) | 3.28 [2.84, 3.71]* | 15% | 4.73 (df = 4) |
| Positive affect | 115 (2) | Std. mean difference (continuous, random, 95% CI) | 0.59 [0.21, 0.98]* | 92% | 12.43 (df = 1)** |
Note: I 2 indicates the level of heterogeneity in the meta‐analysis; ≥70 = considerable heterogeneity.
*
Statistically significant outcome in favour of the natural environment (p < .05).
**
Chi‐squared test indicates significant heterogeneity (p ≤ .10).