Perry, Adrienne2016-11-252016-11-252016-05-122016-11-25http://hdl.handle.net/10315/32674Intensive Behavioural Intervention (IBI) is currently the treatment of choice for young children with moderate to severe Autism Spectrum Disorders. Research has examined different aspects of the intervention, though there is a paucity of information on the quality of IBI. This study examined the York Measure of Quality of IBI (YMQI) in 39 children receiving publicly-funded IBI in Ontario for approximately one year. Videos (n = 402) of children engaged in IBI were coded using the YMQI. A factor analysis showed that the YMQI measures different aspects of IBI quality: Pace and Organization, Technical Correctness, Engagement and Motivation, and Generalization. All of these subscales remained fairly stable, within the good quality range, over approximately one year in IBI, with relatively lower Generalization scores. An examination of the relationships between the YMQI subscales and childrens characteristics at the start of IBI showed that children with more autism symptomatology at the start of treatment receive intervention lower in Engagement and Motivation at the beginning of treatment. In terms of the connection of IBI quality to childrens progress, there was a relationship between Technical Correctness at the start of treatment and greater decreases in autism severity, as well as relationships between Generalization and childrens gains in cognitive skills and decreases in autism severity. Finally, the change in autism symptomatology was predicted by three of the trajectories of quality subscales throughout the year. These results help operationalize the quality of IBI more precisely and have implications for IBI training, supervision, and research.enAuthor owns copyright, except where explicitly noted. Please contact the author directly with licensing requests.Developmental psychologyElectronic Thesis or Dissertation2016-11-25Autism Spectrum Disorder (ASD)Intensive Behavioural Intervention (IBI)Treatment quality