title: Psychometric properties of the Thai version of the 22-item and 45-item Karasek job content questionnaire.
abstract: OBJECTIVE
  To evaluate the validity and reliability of the Thai version of the job content questionnaire (TJCQ) both 22-item and 45-item versions.
  
  
  METHODS
  The study encompassed 10,450 employees in Songkhla province, Thailand. A 45-item job content questionnaire (JCQ) was translated and back translated complying with the JCQ usage policy. TJCQ covers seven scales as follows: psychological demand, decision latitude, supervisor support, coworker support, physical demand, job security and hazard at work. Internal consistency was examined using Cronbach's alpha coefficient. Factor validation was tested using both exploratory and confirmatory factor analysis.
  
  
  RESULTS
  Both 22-item and 45-item versions of TJCQ demonstrated acceptable internal consistency in nearly all scales except for psychological demand. The exploratory and confirmatory factor analysis result gave support to 5-factor model in 22-item version and 8-factor model in 45-item version of TJCQ. The psychological demand scale tended to split into two subscales. Other scales were consistent with the expected dimensions though some items extracted differently along the theoretical dimensions.
  
  
  CONCLUSIONS
  Our study provided evidence for the reliability and validity of the TJCQ among Thai employees and supported the ongoing debate on multifaceted psychological demand and its complexity, making it feasible to extend the TJCQ beyond its original structure.
authors.affiliation: Occupational Health Unit, Department of Community Medicine, Prince of Songkla University, Hatyai, Songkhla, Thailand. pphakthongsuk@gmail.com
authors.forename: Pitchaya
authors.initials: P
authors.lastname: Phakthongsuk
authors.forename: Nualta
authors.initials: N
authors.lastname: Apakupakul
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000175:diagnosis* / Q000453:epidemiology; D011594:Psychometrics / Q000379:methods*; D012931:Social Environment; D013315:Stress, Psychological / Q000175:diagnosis* / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013785:Thailand / Q000453:epidemiology; D017132:Workplace / Q000523:psychology*; D055815:Young Adult