50
scope of the systematic review on indoor plants and psychological wellbeing
Exact: 50 studies
The review synthesised 50 empirical studies across 45 journal papers on the psychological effects of indoor plants
The review covered literature from Web of Science (from 1900 onwards) and WANFANG DATA (from 1980 onwards), including studies written in English and Chinese. Eligible studies had to use quantitative methods, involve indoor plants (real or surrogates) as an intervention, include comparators, and report psychological perceptions as outcomes. This yielded 45 journal papers encompassing 50 individual studies.
The two authors collected 45 journal papers (with 50 studies in total).
Related findings
1.52×
Less greenspace linked to higher odds of cases accepted for child protective services
Census blocks with <10% greenspace had 1.52× the odds of a case being accepted for CPS services compared to blocks with >30% greenspace
Yuan He et al., 2024, Child Abuse & Neglect
1.52×
Less greenspace linked to higher odds of substantiated child maltreatment reports
Census blocks with <10% greenspace had 1.52× the odds of a substantiated CPS report compared to blocks with >30% greenspace
Yuan He et al., 2024, Child Abuse & Neglect
16.1%
nature exposure around schools offers the highest financial return of all interventions tested
Nature exposure achieved the highest return on investment at 16.1% with a 6.2-year payback period
Yingjie Li et al., 2026, SSRN Electronic Journal
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