18577
Measuring Restricted Interests and Repetitive Behaviors in Infant Siblings at-Risk for ASD: Comparing Home Setting Versus Clinic Performance of 12 Month Olds
Approximately 20% of younger siblings of children with autism spectrum disorder (ASD) are at an increased risk for developing ASD (Ozonoff, 2011). According to the DSM-5, ASD symptomatology involves restricted, repetitive patterns of behavior (RRB), interests, or activities; however, these indicators are not yet thoroughly researched in very young siblings. During the second and third year, repetitive hand and finger mannerisms become more pronounced among children with ASD and less pronounced among children with developmental delays (DD) and typical development (TD). (Chawarska & Volkmar, 2005; Evans et al., 1997; Moore & Goodson, 2003; Werner et al., 2005). More recently, Stronach and Wetherby (2012) examined RRB among toddlers at a mean age of 20 months in the clinic and home settings, identifying a higher presence of RRB in the clinic, given the nature of structured probes and repeated presentations of objects.
Objectives:
The purpose of this study was to examine the relationship between home observation and clinical assessment of RRB of 15 (projecting 25 by May 2015) 12-month old infants considered at risk for ASD, given sibling status.
Methods:
High-risk, 12-month old infant siblings were seen for communication assessments as part of a large, federally-funded longitudinal study examining risk and resilience in the first two years. The assessment battery included two samples of early social communication behavior: Communication and Symbolic Behavior Scales (CSBS-DP; Wetherby & Prizant, 1993) video-recorded in a clinic, and a video-recorded home observation. The Systematic Observation of Red Flags of ASD (SORF), an ASD-specific screening instrument, was used to rate early symptomatology within clinic and home observations. Analysis included examining differences/similarities regarding 4 of the 22 SORF red flags, specifically: (1) repetitive movements with objects, (2) repetitive body movements/posturing, (3) sticky attention to objects, and (4) unusual sensory exploration/excessive interest in sensory aspects of environment. Differences in SORF values between clinic/home observations were assessed using paired t-tests and Wilcoxon signed-rank tests. Pearson’s correlation was utilized to gauge linear association between total clinic/home SORF results.
Results:
Pearson’s correlation indicated a moderate but non-significant association between total red flags on home SORF and clinic SORF (r= 0.302; p = 0.246). However, total red flags on home SORFs were significantly lower than clinic SORFs, (p = 0.006). Clinic SORFs picked up significantly more RRB red flags than home SORF (p < 0.001). There was no significant difference for Social Communication and Social Interaction Impairment items on the clinic SORF versus home SORF (p = 0.060). In addition, clinic SORFs revealed significantly higher scores than home SORFs for RRB items including: repetitive movements with objects (p = 0.010), repetitive movements or posturing of body (p = 0.005), sticky attention to objects (p = 0.026), and unusual sensory exploration/excessive interest in sensory aspect of environment (p = 0.016).
Conclusions:
Findings suggest that while the CSBS is primarily examining communication, structured tasks involving objects and communicative temptations may reveal increased amounts of RRB, and therefore, expose earlier symptomatology and provide more quantitative assessment of red flags in this diagnostic domain.