The frequency of restricted and repetitive behaviors in a community sample of 15 month - old infants Running head : repetitive behaviors

Objective: To investigate the frequency and pattern of a wide range of restricted and repetitive behaviors (RRBs) in the second year of life. Method: Parents of 139 15-month-old typically developing infants from a community sample completed the Repetitive Behaviour Questionnaire-2 (RBQ-2), giving information on RRBs (e.g. stereotyped motor movements, sensory interests, routines and rituals and preoccupations with restricted interests) seen in their children. Results: The RBQ-2 was found to be a reliable measure of these behaviors at this age and revealed a high frequency of particular types of repetitive motor movements in 15-month-olds. Conclusion: These findings have implications for the early detection of disorders characterized by high levels of restricted and repetitive behaviors, such as Autism Spectrum Disorder (ASD).