Table 1. Average raw scores for each of the 24-month infant assessments.

SE is shown for both high-risk ASD and non-ASD groups. The number of participants that contributed to each measure is listed in parentheses. The details of the assessments as well as the specific items and subscales are included in Materials and Methods. Behavioral tests included the Repetitive Behaviors Scale–Revised (RBS-R), Mullen Scales of Early Learning (MSEL), and Communication and Symbolic Behavior Scales (CSBS).

Assessmentn (ASD+/ASD)MeasureASDNon-ASD
CSBS: social communication50 (8/42)Social interaction0.75 ± 0.32.51 ± 0.2
CSBS: social communication50 (8/42)Joint attention1.63 ± 0.63.66 ± 0.3
MSEL: cognitive ability57 (10/47)Expressive language18.91 ± 1.420.82 ± 0.6
MSEL: cognitive ability58 (11/47)Fine motor24.08 ± 1.023.84 ± 0.3
MSEL: cognitive ability53 (10/43)Gross motor24.64 ± 0.525.79 ± 0.4
MSEL: cognitive ability57 (10/47)Visual reception20.18 ± 2.023.58 ± 0.6
MSEL: cognitive ability58 (11/47)Receptive language24.42 ± 0.826.53 ± 0.5
RBS-R: repetitive behavior47 (9/38)Self-injurious2.3 ± 1.00.16 ± 0.1
RBS-R: repetitive behavior47 (9/38)Stereotyped3.4 ± 0.80.31 ± 0.1
RBS-R: repetitive behavior47 (9/38)Sameness4.9 ± 0.90.9 ± 0.2
RBS-R: repetitive behavior47 (9/38)Ritualistic2.2 ± 0.50.5 ± 0.1
RBS-R: repetitive behavior47 (9/38)Compulsive3.4 ± 0.40.4 ± 0.1
RBS-R: repetitive behavior47 (9/38)Repetitive1.8 ± 0.90.41 ± 0.1