title: Psychometric properties of the world health organization disability assessment schedule II -12 Item (WHODAS II) in trauma patients.
abstract: BACKGROUND
  The 12-item WHODAS II is widely used for assessing disability among different populations. This study aimed at assessing the psychometric properties of the Persian version of the 12-item WHODAS II among trauma patients.
  
  
  METHODS
  In this methodological study, 220 patients aging 15-65-year-old hospitalized in Shahid Beheshti Hospital, Kashan, Iran, were studied. The WHODAS II was used for data collection. The reliability of this schedule was assessed by evaluating its internal consistency. Its validity was evaluated by using the known-groups approach and the convergent validity method. The exploratory and the confirmatory factor analysis techniques were also used for assessing the factor structure of the schedule.
  
  
  RESULTS
  The mean of participants' ages was 34.7±14.5 years. Most of the participants were male patients (84.1%), had multiple injury (77.7%), and had been injured in road traffic accidents (76.8%). The Cronbach's alpha of the WHODAS II was 0.91, confirming its acceptable internal consistency. Known-groups comparisons revealed that this schedule can satisfactorily differentiate among patients with different severity of trauma (P value<0.0001). The results of exploratory factor analysis showed that the WHODAS II had a two-factor structure while the confirmatory factor analysis revealed that one-factor model fitted the data.
  
  
  CONCLUSIONS
  Study findings suggest that the Persian version of the 12-item WHODAS II is a valid and reliable scale for assessing trauma patients' disability. More Large-scale studies are needed for assessing the validity and the reliability of this schedule among other patients.
authors.affiliation: Ph.D. Candidate of Trauma, Trauma Research Center- Kashan University of Medical Sciences, Kashan, Iran. Electronic address: Abedzadeh@kaums.ac.ir.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Abedzadeh-Kalahroudi
authors.affiliation: Trauma Research Center- Kashan University of Medical Sciences, Kashan, Iran. Electronic address: ebirazi2015@gmail.com.
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Razi
authors.affiliation: Trauma Research Center- Kashan University of Medical Sciences, Kashan, Iran. Electronic address: m.sehat2015@gmail.com.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Sehat
authors.affiliation: School of public health, Tehran University of Medical sciences, Tehran, Iran. Electronic address: asadilari@tums.ac.ir.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Asadi-Lari
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000523:psychology*; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014944:World Health Organization; D014947:Wounds and Injuries / Q000150:complications / Q000503:physiopathology / Q000523:psychology*; D055815:Young Adult
keywords: Disability; Trauma; Validity; WHODAS II; and Iran; reliability