Development and psychometric properties of the Attitudes Toward Intellectual Disability Questionnaire - Short Form.

BACKGROUND: Understanding public attitudes towards people with intellectual disability (ID) can help orient activities to promote the social inclusion of this group. The ATTitudes toward Intellectual Disability (ATTID) questionnaire is a validated 67-item tool used to assess attitudes towards people with ID from a multidimensional perspective. It is based on a five-factor model tapping into cognitive, emotional and behavioural components of attitudes. In order to facilitate international research, the goal of this study was to develop a short version that would retain the long form's psychometric properties. METHODS: Analyses were conducted on a sample of 1608 respondents who completed the full-length ATTID. A four-step test refinement procedure was used to reduce the number of items. The first two steps involved a Cronbach's alpha analysis. Items retained were then reviewed to assess face validity. Correlations between factors were calculated, and a factor analysis was performed to compare the original and short forms. RESULTS: The number of items in the ATTID was reduced from 67 to 35. The short form maintained good overall reliability. The correlational pattern between factors in both the long and short form is generally the same. The factor analysis of the short form showed a similar five-factor structure with some loss of variance. CONCLUSIONS: We recommend the short form be used when administration time is an issue, particularly in a research context. Replication studies with new samples are needed to further assess the psychometric properties of the ATTID-Short Form.