g = -0.67
portable digital nature reduces anxiety
Hedges' g is a standardised effect size, in standard-deviation units
Portable Digital Nature Experience significantly reduces anxiety
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 (simulated nature delivered through screens, audio or other portable media) reduces mental health symptoms. For anxiety specifically, the pooled effect was g = -0.67 (95% CI [-1.01, -0.33], p < .001), the largest reduction among the three outcomes studied, alongside smaller reductions in stress and depression.
For clinicians, healthcare designers and those planning waiting areas, wards or remote care programmes, this points to a low-footprint way to lower anxiety when direct access to green space is limited. The study also found auditory-only nature conditions outperformed multisensory and visual-only formats for anxiety, suggesting sound design specifically, rather than visual richness, may be the more important feature to prioritise when building such interventions.
The estimate rests on 36 trials with considerable variation in intervention design (auditory, visual, multisensory, differing durations and clinical populations), and the confidence interval spans a wide range, from -1.01 to -0.33, meaning the true effect could be much smaller or considerably larger than -0.67. No differences emerged by age, sex, clinical status or intervention duration, but these trials mostly tested short-term exposure, so lasting or real-world effectiveness outside controlled settings remains untested.
- Attention Restoration
- Kaplan ART: soft fascination in natural settings restores directed attention
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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