Individual, behavioural, and environmental determinants of personal light exposure in daily life: A multi-country wearable and experience-sampling study (Analysis Artifact)

Personal light exposure is a modifiable determinant of circadian and neurobehavioural health, yet its everyday structure across populations remains poorly understood. This harmonised, multi-country field study examines ocular light exposure in 191 adults across nine sites in Costa Rica, Germany, Ghana, the Netherlands, Spain, Sweden and Turkey, comprising 1,480 participant-days. Participants wore calibrated light loggers near the corneal plane and at chest level and completed repeated contextual assessments. The study reports that average daytime exposure remained below recommended melanopic levels, adherence varied by site, daily phase and photoperiod, individual and activity-level differences explained more variation than site, and daylight access, outdoor activity and micro-environment were the strongest exposure correlates. If you use this research compendium, manuscript, code, or derived materials, please cite it using the metadata in this file.