title: Assessing environmental features related to mental health: a reliability study of visual streetscape images.
abstract: BACKGROUND
  An association between depressive symptoms and features of built environment has been reported in the literature. A remaining research challenge is the development of methods to efficiently capture pertinent environmental features in relevant study settings. Visual streetscape images have been used to replace traditional physical audits and directly observe the built environment of communities. The aim of this work is to examine the inter-method reliability of the two audit methods for assessing community environments with a specific focus on physical features related to mental health.
  
  
  METHODS
  Forty-eight postcodes in urban and rural areas of Cambridgeshire, England were randomly selected from an alphabetical list of streets hosted on a UK property website. The assessment was conducted in July and August 2012 by both physical and visual image audits based on the items in Residential Environment Assessment Tool (REAT), an observational instrument targeting the micro-scale environmental features related to mental health in UK postcodes. The assessor used the images of Google Street View and virtually "walked through" the streets to conduct the property and street level assessments. Gwet's AC1 coefficients and Bland-Altman plots were used to compare the concordance of two audits.
  
  
  RESULTS
  The results of conducting the REAT by visual image audits generally correspond to direct observations. More variations were found in property level items regarding physical incivilities, with broad limits of agreement which importantly lead to most of the variation in the overall REAT score. Postcodes in urban areas had lower consistency between the two methods than rural areas.
  
  
  CONCLUSIONS
  Google Street View has the potential to assess environmental features related to mental health with fair reliability and provide a less resource intense method of assessing community environments than physical audits.
authors.affiliation: Department of Public Health and Primary Care, Institute of Public Health, Forvie Site, University of Cambridge, School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge CB2 0SR, UK. ytw22@medschl.cam.ac.uk.
authors.forename: Yu-Tzu
authors.initials: YT
authors.lastname: Wu
authors.forename: Paul
authors.initials: P
authors.lastname: Nash
authors.forename: Linda E
authors.initials: LE
authors.lastname: Barnes
authors.forename: Thais
authors.initials: T
authors.lastname: Minett
authors.forename: Fiona E
authors.initials: FE
authors.lastname: Matthews
authors.forename: Andy
authors.initials: A
authors.lastname: Jones
authors.forename: Carol
authors.initials: C
authors.lastname: Brayne
mesh_terms: D003625:Data Collection; D004739:England; D004777:Environment; D004779:Environment Design; D006295:Health Resources; D006794:Household Articles; D006801:Humans; D008377:Maps as Topic; D008603:Mental Health; D015588:Observer Variation; D015203:Reproducibility of Results; D012111:Residence Characteristics; D057386:Search Engine; D014584:User-Computer Interface; D014937:Work