g = -0.26
portable digital nature reduces depression
Hedges' g is a standardised effect size, in standard-deviation units
Portable Digital Nature Experience significantly reduces depression
A three-level meta-analysis pooling 118 effect sizes from 36 randomised controlled trials, covering 2925 participants across 17 countries, examined whether Portable Digital Nature Experience (PDNE), delivered through digital or portable devices rather than real outdoor settings, affects mental health. For depression specifically, PDNE produced a small but statistically significant reduction, g = -0.26 (95% CI [-0.51, -0.01], p = .044), smaller than the reductions found for stress and anxiety in the same analysis.
For those overseeing healthcare, workplace or care settings where access to real green space is limited, this indicates that digitally delivered nature content, screens, audio or portable devices, can lower depressive symptoms to a measurable degree. It offers a scalable substitute where physical nature exposure is impractical, extending restorative environmental design principles into settings such as clinics, offices or institutional interiors.
The evidence is well supported overall, drawing on 36 randomised trials, but the depression effect itself is modest and its confidence interval sits close to zero (-0.51 to -0.01), with a p-value of .044 marking it as only just below the conventional significance threshold. The design shows an aggregate effect across varied populations and delivery formats; it does not establish which specific PDNE format or setting works best for depression.
Healthcare
Results from the three-level meta-analysis indicate that PDNE significantly reduced three common mental health issues, including stress (g = -0.51; 95% CI [-0.73, -0.28]; p < .001), anxiety (g = -0.67; 95% CI [-1.01, -0.33]; p < .001), and depression (g = -0.26; 95% CI [-0.51, -0.01]; p = .044).
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