Table 1.

Participant demographics

Characteristic	Fragile X Syndrome (FXS) M (SD) % (n/N)	Typical Development (TD) M (SD) % (n/N)	Group Comparison
Malea	90% (9/10)	79% (11/14)	–
Caucasianb	80% (8/10)	79% (11/14)	–
Chronological age (months)c	11.18 (1.09)	10.63 (.45)	–
Intelligence Quotientd	52.40 (3.87)	101.38 (7.25)	p ≤ .0025**
Maternal Educatione	5.44 (1.13)	5.83 (.72)	–
Vineland Adaptive Behavior Scales Composite Standard Scoref	61.44 (10.11)	105.15 (11.38)	p ≤ .0001***
Childhood Autism Rating Scaleg	24.16 (3.12)	16.2 (1.21)	p ≤ .0001***
FMRP Levelh	6.94 (6.97)	NA	NA

Note. n/N = number with characteristic / number nonmissing for the group

^aMale: Fisher’s Exact Test, p ≤ .61.

^bCaucasian: Fisher’s Exact Test, p ≤ 1.00.

^cChronological Age (months): Exact Wilcoxon (Mann-Whitney) test S = 186, exact p ≤ .2262.

^dIQ: Missing 5 FXS & 7 TD; 0=Average/Above Average Intelligence (standard scores above 85); 1=Borderline (70-84); 2 = Mild Intellectual Disability (ID; 55-69); 3=Moderate ID (40-54); 4=Severe/Profound ID (<39); Exact Wilcoxon (Mann-Whitney) test S =15, exact p ≤ .0025.

^eMaternal Education: Missing 1 FXS & 2 TD; 1 = 6th grade or lower; 2 = 7th to 9th grade; 3 = partial high school; 4 = high school graduate/GED; 5 = associate of arts/associate of science or technical training or partial college training; 6 = bachelor of arts/science; 7 = master of arts/science or doctorate or other professional degree completed; Exact Wilcoxon (Mann-Whitney) test S = 87, exact p ≤ .4415.

^fVABS ABC SS: Missing 1 FXS & 1 TD; Exact Wilcoxon (Mann-Whitney) test S = 45, exact p ≤ .0001.

^gCARS: Missing 1 FXS and 4 TD; Exact Wilcoxon (Mann-Whitney) test S = 134.5, exact p ≤ .0001.

^hFMRP: Missing 2 FXS; TD not applicable.

^*p < .05

^**p < .01

^***p < .001