title: Psychometric properties of the Nottwil Environmental Factors Inventory Short Form.
abstract: OBJECTIVE
  To examine the psychometric properties of the Nottwil Environmental Factors Inventory Short Form using Rasch analysis; to determine its construct validity and internal consistency; and to develop a metric for scoring.
  
  
  METHODS
  Cross-sectional psychometric study. Construct validity of the Nottwil Environmental Factors Inventory Short Form, including model fit, person and item fit, local item dependence, dimensionality, and differential item functioning (DIF), was investigated with Rasch analysis. Internal consistency was assessed with Cronbach alpha and item-total correlations.
  
  
  METHODS
  Community.
  
  
  METHODS
  Swiss residents aged >16 years and living with traumatic or nontraumatic spinal cord injury (SCI) (N=1549).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  The Nottwil Environmental Factors Inventory Short Form, a 14-item questionnaire developed to assess perceived impact of environmental barriers on participation.
  
  
  RESULTS
  Local dependencies between items addressing a similar content could be solved by creating a testlet. With 1 testlet there was strong evidence for unidimensionality of the Nottwil Environmental Factors Inventory Short Form. Although person-item targeting revealed a floor effect, indicating few perceived environmental barriers to participation in the Swiss SCI population, the item fit was good. Only a few items presented DIF. The Nottwil Environmental Factors Inventory Short Form showed good internal consistency (α=.82).
  
  
  CONCLUSIONS
  This psychometric analysis supports the use of the Nottwil Environmental Factors Inventory Short Form to evaluate perceived environmental barriers to participation in persons with SCI living in the community.
authors.affiliation: Swiss Paraplegic Research, Nottwil, Switzerland; Department of Health Sciences and Health Policy, University of Lucerne, Luzern, Switzerland.
authors.forename: Carolina S
authors.initials: CS
authors.lastname: Ballert
authors.affiliation: Swiss Paraplegic Research, Nottwil, Switzerland; Brain Center Rudolf Magnus and Center for Excellence in Rehabilitation Medicine, University Medical Center Utrecht and De Hoogstraat Rehabilitation, Utrecht, The Netherlands.
authors.forename: Marcel W
authors.initials: MW
authors.lastname: Post
authors.affiliation: Swiss Paraplegic Research, Nottwil, Switzerland; Department of Health Sciences and Health Policy, University of Lucerne, Luzern, Switzerland.
authors.forename: Martin W
authors.initials: MW
authors.lastname: Brinkhof
authors.affiliation: Swiss Paraplegic Research, Nottwil, Switzerland; Department of Health Sciences and Health Policy, University of Lucerne, Luzern, Switzerland; Institute for Disaster Management and Reconstruction of Sichuan University and Hong Kong Polytechnic University, Chengdu, Sichuan Province, China. Electronic address: jan.reinhardt@paraplegie.ch.
authors.forename: Jan D
authors.initials: JD
authors.lastname: Reinhardt
mesh_terms: D000328:Adult; D000368:Aged; D001290:Attitude; D003430:Cross-Sectional Studies; D006233:Persons with Disabilities; D004779:Environment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D015203:Reproducibility of Results; D058992:Social Participation; D013119:Spinal Cord Injuries / Q000523:psychology*; D011795:Surveys and Questionnaires; D013557:Switzerland
keywords: Environment; International Classification of Functioning, Disability and Health; Psychometrics; Rehabilitation; Social participation; Spinal cord injuries