How Do Early ASD Screening Scores Relate with Motor and Language Development in a Community Sample?

Background: Early screening for autism spectrum disorders (ASD) has been primarily studied in high risk populations. Less is known about the validity of such tools in low-risk infants and their correspondence with developmental discontinuity (i.e. increase or decrease beyond normative expectations). Different types of markers may assist in identifying infants with different developmental needs.

Objectives: To determine the association of ASD risk on a parent questionnaire at 12-months with (1) concurrent developmental status, as well as with (2) increase or decrease in specific developmental areas from 13 to 30 months.

Methods: Seventy-six infants (55% boys) had the First Year Inventory (FYI) completed by their parents at 12 months. The FYI consists of a social-communication risk score and a sensory-regulatory risk score. The Mullen Scales of Early Learning (MSEL) was administered at 13- and 30-months. Toddlers were classified as stable, increasing, or decreasing by at least 1.5 standard deviations (SD) on their developmental quotient (DQ) scores in each of the five MSEL areas from 13 to 30 months. Between 3.9%-51.3% of the sample was classified as increasing, and 0-23.7% as decreasing across areas.

Results: Of those with decreasing scores in the Gross Motor, Fine Motor and Expressive Language areas 22%, 19%, and 25% respectively had a developmental diagnosis at 30 months including ASD. There was not a higher rate of children with FYI risk in the decreasing versus stable and increasing groups. Higher FYI social-communication risk scores were associated with lower MSEL DQ scores at 13 months (Gross Motor r(76)=-.20, p=.08; Fine Motor r(76)=-.30, p=.01; Visual Perception r(76)=-.28, p=.02; Receptive Language r(76)=-.58, p<.001; Expressive Language r(76)=-.43, p<.001) and at 30 months (Gross Motor r(76)=-.40, <.001; Receptive Language r(76)=-.33, p<.001; Expressive Language r(76)=-.38, p<.001). The FYI sensory-regulatory risk score was not associated with MSEL scores at 13 months and modestly correlated with Receptive Language at 30 months, r(76)=-.23, p=.03.

FYI social-communication and sensory-regulatory scores were compared between the MSEL difference groups. Of all MSEL area difference groups, independent sample t-tests showed that children in the Gross Motor decreasing group had significantly higher sensory-regulatory risk scores than children in the stable group (M=19.51, SD=10.79, M=13.13, SD= 9.24 respectively, t(70)=-2.43, p=.02, d=0.64). For Receptive Language, children in the increasing group had significantly lower risk on the sensory-regulatory domain than in the stable group (M=12.33, SD=9.55, M=17.32, SD= 9.61 respectively, t(74)=2.27, p=.03, d=0.52).

Conclusions:  A decrease in developmental status beyond normative expectations was not necessarily an 'alarming' signal.  FYI social-communication risk was associated with developmental status at each age but did not explain change over 18 months. Elevated sensory-regulatory risk characterized infants who showed a decrease in their gross motor skills while reduced risk in this area characterized infants who increased in their receptive language. Sensory-regulatory risk status may play a pivotal role in shaping developmental change.