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Record W4415943346 · doi:10.1136/bmj-2025-084618

Greenness and hospital admissions for cause specific mental disorders: multicountry time series study

2025· article· en· W4415943346 on OpenAlexaffabout
Tingting Ye, Wenzhong Huang, Zhihu Xu, Rongbin Xu, Pei Yu, Yi-Shan Wu, Yiwen Zhang, Wenhua Yu, Yanming Liu, Bo Wen, Ke Ju, Zhengyu Yang, Shuang Zhou, Samuel Hundessa, Simon Hales, Éric Lavigne, Patricia Matus Correa, Kraichat Tantrakarnapa, Ho Kim, Micheline de Sousa Zanotti Stagliorio Coêlho, Paulo Hilário Nascimento Saldiva, Yuming Guo, Shanshan Li

Bibliographic record

VenueBMJ · 2025
Typearticle
Languageen
FieldEnvironmental Science
TopicUrban Green Space and Health
Canadian institutionsUniversity of OttawaHealth Canada
FundersMedical Research CouncilNational Health and Medical Research CouncilNational Research Council of ThailandChina Scholarship Council
KeywordsMEDLINEMental healthAdverse effectHospital admissionSeries (stratigraphy)

Abstract

fetched live from OpenAlex

OBJECTIVES: To examine the association between exposure to greenness and hospital admissions for mental disorders, and to estimate greenness related hospital admissions under various greenness intervention scenarios. DESIGN: Multicountry time series study. SETTING: 6842 locations in seven countries (Australia, Brazil, Canada, Chile, New Zealand, South Korea, and Thailand). PARTICIPANTS: 11.4 million hospital admissions for mental disorders, 2000-19. MAIN OUTCOME MEASURES: Hospital admissions for all cause mental disorders and for six categories in relation to greenness (measured by the normalised difference vegetation index (NDVI)): psychotic disorders, substance use disorders, mood disorders, behavioural disorders, dementia, and anxiety. Associations were estimated using quasi-Poisson regression models, controlled for weather conditions, air pollutants, socioeconomic indicators, seasonality, and long term trends. Models were stratified by sex, age, urbanisation, and season. Hospital admissions were estimated under different greenness intervention scenarios. RESULTS: During 2000-19, of hospital admissions related to mental health disorders, 30.8% (3 522 749 patients) were for psychotic disorders, 24.7% (2 821 860) for substance use disorders, 11.6% (1 325 305) for mood disorders, 7.4% (845 561) for behavioural disorders, 3.0% (348 149) for dementia, and 2.5% (283 914) for anxiety. A 0.1 increase in NDVI was associated with a 7% reduction in the risk of hospital admissions for all cause mental disorders (relative risk 0.93, 95% confidence interval (CI) 0.89 to 0.98) in pooled analyses. However, associations varied across countries and disorder types. Brazil, Chile, and Thailand showed consistent protective associations across most disorder categories, while modest adverse (ie, harmful) associations were observed in Australia and Canada for hospital admissions for all cause mental disorders and for several specific disorder categories. Exposure-response analyses showed a generally monotonic and approximately linear relation without clear thresholds. When limited to urban settings where associations were generally more consistent, an estimated 7712 (95% CI 6701 to 8726) hospital admissions for mental health disorders annually in urban areas were statistically attributable to observed greenness levels. Analysis by greenness intervention scenarios in urban areas suggested that a 10% increase in greenness was associated with reductions in hospital admissions for mental disorders ranging from ~1 per 100 000 in South Korea to ~1000 per 100 000 in New Zealand. CONCLUSIONS: Greenness was statistically associated with lower risks of hospital admissions for mental disorders in several countries, particularly in urban settings. Some adverse associations were, however, observed, and findings were heterogeneous across contexts.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.002
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.033
Threshold uncertainty score0.065

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0010.002
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.001
Bibliometrics0.0010.001
Science and technology studies0.0000.000
Scholarly communication0.0010.001
Open science0.0010.001
Research integrity0.0000.001
Insufficient payload (model declined to judge)0.0010.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.012
GPT teacher head0.287
Teacher spread0.275 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations1
Published2025
Admission routes2
Has abstractyes

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