Pragmatic abilities in children with neurodevelopmental disorders: development of Pragmatic Abilities Questionnaire based on the Rasch rating scale model

BACKGROUND: Pragmatic abilities includes a set of skills that could vary by culture and which are absolutely essential for social communication. These abilities can be impaired in many children with neurodevelopmental disorders and may lead to educational and psychological difficulties. Assessing pragmatic abilities requires valid and reliable instruments that should be developed with cultural differences in mind. PURPOSE: This paper reports on the development of a new instrument for measuring and evaluating pragmatic abilities in children with neurodevelopmental disorders. METHODS AND PARTICIPANTS: The questionnaire items were generated based on a literature review on the theoretical basis of pragmatic abilities, the available pragmatic assessment instruments, interviews with experts and the mothers of children with neurodevelopmental disorders and the observation of their interaction with children based on the pragmatic protocol. Item selection and reliability and validity assessment for the instrument were carried out based on the Rasch rating scale model analysis. The Pragmatic Abilities Questionnaire (PAQ) was completed by the mothers of 185 normally-developing children and the mothers of 120 children with neurodevelopmental disorders, including Autism Spectrum Disorder (ASD), Specific Language Impairment (SLI), Attention-Deficit/Hyperactivity Disorder (ADHD) and Social (Pragmatic) Communication Disorder (SPCD). RESULTS: The initial pool of 119 items, reflecting the characteristics of pragmatic abilities, was first reduced to 80 after a review by ten experts, and then further reduced to 40 using the Rasch analysis for removing the misfitting items. The final PAQ had a person measure reliability of 0.97 with a separation of 6.03 and an item measure reliability of 0.99. The remaining items formed the questionnaire and measured a single construct, which explained 63.8% of the variance. CONCLUSION: The 40 items of the PAQ appear to construe a psychometrically-sound measure of pragmatic abilities.