Table 1.
Study and sample characteristics.
| STUDY/Sample, place, year of data collection/publication | Valid N (after excl. Participants with incomplete BDS data and outliers) | Age | Gender | Env W or B Subj Factor | Env stimuli and duration | Env info | BDS admin (max test score) | Attrition/outliers |
|---|---|---|---|---|---|---|---|---|
| 1. Walk, UM. (Berman et al., 2008) | 37 UM students | M = 22.62 y (before excl 1 outlier) | 23 F, 15 M (before excl 1 outlier) | W | Walk, 50–55 min | Nature: Nichols Arboretum, Ann Arbor. Urban: Downtown Ann Arbor. Michigan, USA | AS, VerbR, IPT (14) | 1 outlier |
| 2. Picture study, UM. (Berman et al., 2008) | 12 UM students | M = 24.25 y | 8 F, 4 M | W | Pic, 10 min | Nature: scenery of Nova Scotia. Urban: pictures of Ann Arbor, Detroit, and Chicago. | AS, VerbR, IPT (14) | |
| 3. Walk, healthy sample, UM, 2011. | 21 UM students | M = 23.62 y, SD = 6.62 | 11 F, 10 M | W | Walk, 50–55 min | Nature: Nichols Arboretum, Ann Arbor. Urban: Downtown Ann Arbor. Michigan, USA | AS, VerbR, IPT (14) | |
| 4. Walk, MDD sample, UM. (Berman et al., 2012) | 19 diagnosed with MDD, from UM and greater Ann Arbor area. | M = 26 y (before excl of 1 participant) | 12 (63.2%) F, 7 (36.8%) M | W | Walk, 50–55 min | Nature: Nichols Arboretum, Ann Arbor. Urban: Downtown Ann Arbor. Michigan, USA | AS, VerbR, IPT (14) | 1 outlier |
| 5. Picture study, UC, 2015. | 45 UC undergrad.students | M = 19.84, SD = 1.07 | 29 F, 16 M | W | Pic, 8–10 min | 50 Nature vs. 50 Urban/built environment pictures. | AS, KR, CT (14) | 1 outlier |
| 6. Picture study, UM, 2015. | 37 UM undergrad.students | Missing | 30 F, 7 M | W | Pic, 8–10 min | 50 Nature vs. 50 Urban/built environment pictures. | AS, KR, CT (14) | 1 outlier |
| 7. Walk, UC, 2016. | 49 UC undergrad students | 18–26 y, M = 19.57, SD = 1.81 | 31 (63.3%) F, 18 (36.7%) M | W | Walk, 15–20 min | Nature: Univ. of Chicago main quadrangles (grass, trees, pond). Urban: walk along the streets outside of the Univ. Of Chicago main quadrangles. | AS, KR, CT (18) | 6 excluded due to doing the wrong walk. |
| 8. Virtual Reality (VR) study 1, UC, 2016. | 82 UC undergrad students | 18–24 y, M = 19.67, SD = 1.70 | 47 F, 32 M (3 missing) | W | VR, 10 min | Nature: VR path with surrounding trees, grass and water ponds. VR Urban: city block with streets and buildings. | AS, KR, CT (18) | 1 outlier |
| 9. Virtual Reality study 2- with habituation, UC, 2016. | 82 UC undergrad students | 18–28 y, M = 19.57 y, SD = 3.76 (missing age for 19 participants) | 53 F, 29 M | B | VR, 10 min | Ibid. Session 1's = VR vs. no-VR habituation in control/space env., session 2's = Nature or Urban VR env. | AS, KR, CT (18) | 1 outlier |
| 10. Composite study- Sounds. UC. (Van Hedger et al., 2018) | 44 UC undergrad students | 18–44 y, M = 21.35, SD = 4.34 | 24 F, 17 M, 3 no answer | B | Sounds, 20–25 min | Nature: nature sounds, e.g., bird song. Urban: urban sounds, e.g., traffic) | AS or VS, KR, CT (14) | |
| 11. Composite study- Pictures. UC, 2016. | 40 UC undergrad students | 18–31 y, M = 21.13, SD = 3.06 | 28 F, 12 M | B | Pic, 20–25 min | Nature: 100 pics of nature scenes. Urban: 100 pics of built environment scenes. | AS or VS, KR, CT (14) | |
| 12. Video study, UBC. (Bourrier et al., 2018) | 60 (+30 in a control condition) from UBC human subject pool, the Reservax subject pool and poster advertising. | 17–45 y, M = 21.1, SD = 3.54 | 67 (74 %) F, 23 M | B | Video (no sound), 10 min | Nature: Banff National Park tour, Alberta Canada. Urban: Tour of Barcelona. | VS, KR, CT (14) | |
| 13. Picture dose study- Session 1 and 2, UM 2009. | 39 UM undergrad.students | Missing | Missing | Nature × 2 sessions | 25–100 pics, 5–20 min | Short = 25 pics, 4–5 min; Medium = 50 pics, 8–10 min; Long = 100 pics, 16–20 min. | AS, VerbR, CT (14) | 2 did not do 2nd session |
| Total, env studied as a W factor (study 1–8) | 302 | |||||||
| Total env studied as a B factor (study 9–12, excl Pic dose study) | 226 | |||||||
| Grand Total | 567 (+30) |
Env, Environment condition; W, within-participant factor; B, between-participant factor; UM, Univ. of Michigan; UC, Univ. of Chicago; MDD, major depressive disorder; IPT, in-person testing; CT, computerized test (using E-prime); AS, auditory stimuli; VerbR, verbal response; KR, keypress response.