Table 1 Demographic and clinical characteristics of participants (means, standard deviations, and ranges)

Race

Black or African American: 1

White/Caucasian: 21

Asian or Pacific Islander: 1

Multiracial: 2

Black or African American: 5

White/Caucasian: 63

Asian or Pacific Islander: 2

Multiracial: 6

χ² = 1.99, p = .57

Maternal education

High school or less: 0.04% (n = 1)

Bachelor’s or less: 36% (n = 9)

Graduate degree: 40% (n = 10)

Not reported: 20% (n = 5)

High school or less: 5.3% (n = 4)

Bachelor’s or less: 60.5% (n = 46)

Graduate degree: 31.6% (n = 24)

Not reported: 2.6% (n = 2)

χ² = 2.14, p = .34

Age (years)

10.66 (1.59)

8.6–14.1

10.15 (2.15)

6.1–15.1

p = .29

d = -.25

Full-Scale IQ

106.24 (11.88)

78–131

103.71 (14.83)

73–148

p = .44

d = − .18

Verbal IQ

106.64 (12.86)

79–134

105.00 (14.64)

71–150

p = .62

d = -.12

Non-verbal IQ

106.24 (13.76)

73–133

103.70 (14.87)

72–143

p = .45

d = − .17

ADOS-2 Total

10.92 (5.04)

3–23

11.89 (4.64)

4–24

p = .39

d = .20

ADOS-2 SA

Total

8.28 (4.19)

3–17

9.21 (4.06)

3–19

p = .33

d = .23

ADOS-2 RRB

Total

2.64 (1.87)

0–7

2.66 (1.65)

0–7

p = .96

d = .01

SCQ Total

19.96 (5.95)

8–31

19.29 (7.23)

5–38

p = .68

d = -.26

SRS-2 Total

78.04 (9.92)

57–91

71.01 (11.29)

46–90

p = .009*

d = − .64

SRS-2 Social Awareness

74.48 (9.54)

58–90

68.36 (10.78)

45–90

p = .02*

d = − .58

SRS-2 Social Cognition

74.04 (12.61)

49–90

67.99 (10.61)

48–90

p = .03*

d = − .54

SRS-2 Social Communication

77.43 (10.57)

52–90

69.84 (11.90)

45–90

p = .008*

d = − .65

SRS-2 Social Motivation

71.65 (11.64)

51–90

65.44 (11.92)

40–103

p = .03*

d = − .52

SRS-2 Restricted Interests and Repetitive Behaviors

77.13 (12.16)

50–98

71.03 (11.98)

46–90

p = .03*

d = − .51

SRS-2 Social Communication and Interaction

77.30 (9.78)

56–90

70.31 (11.12)

46–90

p = .009*

d = − .65

VABS Communication Standard Score

87.40 (12.21)

65–108

86.92 (13.52)

62–125

p = .88

d = − .04

VABS Socialization Standard Score

73.60 (11.92)

58–112

77.22 (14.92)

36–119

p = .25

d = .27