Examining the Validity of the Model of Human Occupation Screening Tool: Using Classical Test Theory and Item Response Theory

Introduction: This study examined the psychometric properties of the Model of Human Occupation Screening Tool, using both item response theory and classical test theory. Method: One hundred and one people with mental health problems, aged 18–65 years, were recruited. The Chinese version of the Model of Human Occupation Screening Tool, the National Taiwan University Hospital Symptom Checklist, the Volitional Questionnaire, the Assessment of Communication and Interaction Skills, and the Mini Mental State Examination were administered. Rasch analysis and correlational analysis were used to examine the construct, convergent, divergent validity and known group validity. Results: Rasch analysis confirmed that there were six subscales within the Chinese version of Model of Human Occupation Screening Tool. The Volitional Questionnaire strongly correlated with the volition subscale (r = 0.583). The Assessment of Communication and Interaction Skills strongly correlated with the communication and interaction subscale (r = 0.815). The Mini Mental State Examination was moderately correlated with the process subscale (ρ = 0.334) and the symptomatology was not associated with any of the subscales as expected. There were significant differences on selected subscale scores across four known groups of participants. Conclusion: The Chinese version of the Model of Human Occupation Screening Tool was valid when applied to people with mental health problems.