title: Rasch analysis of the Chedoke-McMaster Attitudes towards Children with Handicaps scale.
abstract: Aim To assess whether the Chedoke-McMaster Attitudes towards Children with Handicaps (CATCH) 36-item total scale and subscales fit the unidimensional Rasch model. Method The CATCH was administered to 1881 children, aged 7-16 years in a cross-sectional survey. Data were used from a random sample of 416 for the initial Rasch analysis. The analysis was performed on the 36-item scale and then separately for each subscale. The analysis explored fit to the Rasch model in terms of overall scale fit, individual item fit, item response categories, and unidimensionality. Item bias for gender and school level was also assessed. Revised scales were then tested on an independent second random sample of 415 children. Results Analyses indicated that the 36-item overall scale was not unidimensional and did not fit the Rasch model. Two scales of affective attitudes and behavioural intention were retained after four items were removed from each due to misfit to the Rasch model. Additionally, the scaling was improved when the two most negative response categories were aggregated. There was no item bias by gender or school level on the revised scales. Items assessing cognitive attitudes did not fit the Rasch model and had low internal consistency as a scale. Conclusion Affective attitudes and behavioural intention CATCH sub-scales should be treated separately. Caution should be exercised when using the cognitive subscale. Implications for Rehabilitation The 36-item Chedoke-McMaster Attitudes towards Children with Handicaps (CATCH) scale as a whole did not fit the Rasch model; thus indicating a multi-dimensional scale. Researchers should use two revised eight-item subscales of affective attitudes and behavioural intentions when exploring interventions aiming to improve children's attitudes towards disabled people or factors associated with those attitudes. Researchers should use the cognitive subscale with caution, as it did not create a unidimensional and internally consistent scale. Therefore, conclusions drawn from this scale may not accurately reflect children's attitudes.
authors.affiliation: a Peninsula Cerebra Research Unit (PenCRU), University of Exeter Medical School, University of Exeter , Exeter , UK.|b NIHR PenCLAHRC, University of Exeter Medical School, University of Exeter , Exeter , UK.
authors.forename: Megan
authors.initials: M
authors.lastname: Armstrong
authors.affiliation: a Peninsula Cerebra Research Unit (PenCRU), University of Exeter Medical School, University of Exeter , Exeter , UK.|b NIHR PenCLAHRC, University of Exeter Medical School, University of Exeter , Exeter , UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Morris
authors.affiliation: b NIHR PenCLAHRC, University of Exeter Medical School, University of Exeter , Exeter , UK.|c Psychology Applied to Health (PAtH), University of Exeter Medical School, University of Exeter , Exeter , UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Tarrant
authors.affiliation: b NIHR PenCLAHRC, University of Exeter Medical School, University of Exeter , Exeter , UK.|c Psychology Applied to Health (PAtH), University of Exeter Medical School, University of Exeter , Exeter , UK.
authors.forename: Charles
authors.initials: C
authors.lastname: Abraham
authors.affiliation: d Psychometric Laboratory for Health Sciences, Faculty of Medicine and Health , Leeds General Infirmary, University of Leeds , Leeds , UK.
authors.forename: Mike C
authors.initials: MC
authors.lastname: Horton
mesh_terms: D000293:Adolescent; D001290:Attitude; D015982:Bias; D002648:Child; D003430:Cross-Sectional Studies; D019988:Children with Disabilities / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D011594:Psychometrics; D011795:Surveys and Questionnaires
keywords: Attitudes; Chedoke–McMaster Attitudes towards Children with Handicaps scale; Rasch model; disability