title: Impact of windows and daylight exposure on overall health and sleep quality of office workers: a case-control pilot study.
abstract: OBJECTIVE
  This research examined the impact of daylight exposure on the health of office workers from the perspective of subjective well-being and sleep quality as well as actigraphy measures of light exposure, activity, and sleep-wake patterns.
  
  
  METHODS
  Participants (N = 49) included 27 workers working in windowless environments and 22 comparable workers in workplaces with significantly more daylight. Windowless environment is defined as one without any windows or one where workstations were far away from windows and without any exposure to daylight. Well-being of the office workers was measured by Short Form-36 (SF-36), while sleep quality was measured by Pittsburgh Sleep Quality Index (PSQI). In addition, a subset of participants (N = 21; 10 workers in windowless environments and 11 workers in workplaces with windows) had actigraphy recordings to measure light exposure, activity, and sleep-wake patterns.
  
  
  RESULTS
  Workers in windowless environments reported poorer scores than their counterparts on two SF-36 dimensions--role limitation due to physical problems and vitality--as well as poorer overall sleep quality from the global PSQI score and the sleep disturbances component of the PSQI. Compared to the group without windows, workers with windows at the workplace had more light exposure during the workweek, a trend toward more physical activity, and longer sleep duration as measured by actigraphy.
  
  
  CONCLUSIONS
  We suggest that architectural design of office environments should place more emphasis on sufficient daylight exposure of the workers in order to promote office workers' health and well-being.
authors.affiliation: School of Architecture, University of Illinois at Urbana-Champaign, Champaign, IL.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Boubekri
authors.affiliation: Department of Neurology, Northwestern University, Chicago, IL.
authors.forename: Ivy N
authors.initials: IN
authors.lastname: Cheung
authors.affiliation: Department of Neurology, Northwestern University, Chicago, IL.
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Reid
authors.affiliation: School of Architecture, University of Illinois at Urbana-Champaign, Champaign, IL ; Department of Architecture, Hwa-Hsia Institute of Technology, Taipei, Taiwan.
authors.forename: Chia-Hui
authors.initials: CH
authors.lastname: Wang
authors.affiliation: Department of Neurology, Northwestern University, Chicago, IL.
authors.forename: Phyllis C
authors.initials: PC
authors.lastname: Zee
mesh_terms: D056044:Actigraphy; D000328:Adult; D016022:Case-Control Studies; D005160:Facility Design and Construction; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012890:Sleep; D013472:Sunlight; D011795:Surveys and Questionnaires; D017132:Workplace / Q000523:psychology; D055815:Young Adult
keywords: architectural design; light exposure; office environment; quality of life; sleep quality