Development and initial validation of the Preschool Imitation and Praxis Scale (PIPS)

The goal of this study was to develop and subsequently evaluate the internal construct and criterion-related validity of the Preschool Imitation and Praxis Scale (PIPS). Different task characteristics were selected considered to be important as unravelled in research in apraxic adults to tap a broad range of possible imitation mechanisms. Participants included 498 children without disabilities (1–4.9 years) and 47 children with autism spectrum disorders (ASD) (1.9–4.5 years). Exploratory factor analysis disclosed 4 dimensions in the scale, labelled: goal directed versus non-goal directed procedural imitation and single versus sequential bodily imitation. Internal consistency for the PIPS scale (α = .97) and subscales was high (α ranged from .79 to .96). In both samples, the PIPS scale score was strongly related to age (r = .78, respectively r = .56). Significant relationships between the PIPS score and mental, language, motor ages in the ASD sample supported criterion-related validity (r ranged from .59 to .74). The PIPS appears to have fundamentally sound psychometric characteristics, although more research is needed.