Pre-registration: Passenger Density on Stockholm Subway Platforms With and Without Blue-Light Exposure: A Quasi-experimental Observational Study
type: Dataset
description: This dataset contains observational count data on passenger presence on subway platforms in the Stockholm metro system, collected as part of a quasi-experimental field study examining behavioural responses to blue LED lighting, BLED. Data were collected at four platforms across three subway stations between September 2025 and April 2026. Two platforms were equipped with blue LED luminaires and two served as non-exposed control platforms. Note: For the purpose of preregistration and documentation, the files provided at this stage contain simulated data only. These simulated files mirror the structure, variables, formats, and temporal alignment of the real data that will be analysed once data collection is complete. The core data consist of time stamped detections from the station camera system, provided as event level logs that is aggregated to minute-by-minute counts. For each platform, two zones were defined within the camera system, an exposure zone located at the platform end where trains enter the station and an adjacent reference zone with standard lighting. Automated video analytics identified human presence within these zones and recorded detections over time. The dataset does not include images, video recordings, or individual level tracking, only anonymised numerical event counts that can be summarised to passenger density measures. Lighting conditions at the exposed platforms alternated between BLED switched on and switched off, primarily in two-week periods with one four-week period, allowing within platform and between platform comparisons over time. Each camera based observation is time stamped and linked to station, platform, zone, experimental condition, and period identifiers. The dataset also includes aggregated station passage data derived from ticket gate systems at the same stations. These data describe the number of passengers entering and exiting each station at minute resolution and serve as indicators of overall station usage that can be alig…
conditions of access: http://publications.europa.eu/resource/authority/access-right/PUBLIC
conditions of access: info:eu-repo/semantics/openAccess
creative work status: completed
  type: DefinedTerm
  in defined term set: http://publications.europa.eu/resource/authority/dataset-status
  term code: COMPLETED
creator: Danielle Berglund
creator: Gergö Hadlaczky
creator: Jesper Alvarsson-Hjort
date modified: 2026-05-28
date published: 2026-05-21
funding: Blue Light on Railways for Suicide Prevention Purposes
  type: Grant
  identifier: TRV 2024/29082, ID 2023-47
  funder: Swedish Transport Administration
language: English
is part of: https://doi.org/10.48723/69yd-5q04
keywords: PSYCHOLOGY
keywords: Psychology (Excluding Applied Psychology)
  type: DefinedTerm
  term code: 50101
keywords: Blue Light
keywords: Suicide Prevention
license: https://creativecommons.org/licenses/by/4.0/
publisher: Karolinska Institutet
size: QuantitativeValue
  unit text: variables
  value: 22
spatial coverage: Stockholm County
temporal coverage: 2025-09-15/2026-04-26
distribution: data/BLISP_Passenger density_Hypotheses_260428.pdf
  type: DataDownload
  additional type: data
  conditions of access: http://publications.europa.eu/resource/authority/access-right/PUBLIC
  conditions of access: info:eu-repo/semantics/openAccess
  content size: 114719
  encoding format: application/pdf
distribution: data/Platform density events - SIMULATED.csv
  type: DataDownload
  additional type: data
  conditions of access: http://publications.europa.eu/resource/authority/access-right/PUBLIC
  conditions of access: info:eu-repo/semantics/openAccess
  content size: 12869381
  encoding format: text/csv
distribution: data/Solar irradiance at Bredäng station 250901-260427.csv
  type: DataDownload
  additional type: data
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  conditions of access: info:eu-repo/semantics/openAccess
  content size: 257455
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distribution: data/Station passages - SIMULATED.csv
  type: DataDownload
  additional type: data
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  content size: 23308769
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distribution: documentation/Ethix_research_plan_Study2.pdf
  type: DataDownload
  additional type: documentation
  conditions of access: http://publications.europa.eu/resource/authority/access-right/PUBLIC
  conditions of access: info:eu-repo/semantics/openAccess
  content size: 363152
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distribution: documentation/README.txt
  type: DataDownload
  additional type: documentation
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version: 1

PropertyValue
property ID: DOI
value: 10.48723/028g-3y46

principalRegistrationNumber
type: PropertyValue
property ID: https://www.rikstermbanken.se/termposter/1848/diarienummer
value: 4-652/2026

Danielle Berglund
type: Person
affiliation: Karolinska Institutet
family name: Berglund
given name: Danielle

Karolinska Institutet
type: Organization
department: Department of Learning, Informatics, Management and Ethics (LIME)

Gergö Hadlaczky
type: Person
affiliation: Karolinska Institutet
family name: Hadlaczky
given name: Gergö

Jesper Alvarsson-Hjort
type: Person
affiliation: Karolinska Institutet
family name: Alvarsson-Hjort
given name: Jesper

Swedish Transport Administration
type: Organization

English
type: Language
alternate name: eng

PSYCHOLOGY
type: DefinedTerm
term code: Psychology

PSYCHOLOGY
type: DefinedTerm

UNDERGROUND RAILWAYS
type: DefinedTerm

SUICIDE
type: DefinedTerm

TRANSPORT ACCIDENTS
type: DefinedTerm

Blue Light
type: DefinedTerm
description: That portion of the electromagnetic spectrum with wavelengths between 450 to 495 nm. Exposure to blue light at night can suppress the secretion of melatonin, disrupt sleep, and cause shifts in CIRCADIAN RHYTHM.
term code: D000095743

Suicide Prevention
type: DefinedTerm
description: Specific strategies for averting suicides. These include mental HEALTH PROMOTION and monitoring PSYCHOLOGICAL WELL-BEING and other intervention programs targeting susceptible individuals.
term code: D000092864

Stockholm County
type: Place