Table 5 Optimal Splits and Mean/Median Age at First Diagnosis Above/Below Split

Delayed speech

5.75

34.9

63.7

0.00000

30

58

Delayed response to own name

3.85

35.6

60.4

0.00000

32

52

Poor eye contact

6.15

40.5

52.1

0.00000

33

42

Lack of gestures

6.05

33.6

56.7

0.00000

30

48

Difficulty understanding gestures

3.75

41.1

54.9

0.00000

34

47

Preference to play alone

7.55

42.3

50.7

0.00000

36

40

Too focused on objects

1.05

44.8

61.6

0.00000

36

54

Poor social skills

5.25

43.2

53.9

0.00000

36

42

Unusual play with toys or objects

5.55

41.3

52.7

0.00000

35

42

Need for sameness

2.35

47.4

35.1

0.00000

38

31

Unusual motor mannerisms

3.15

42.6

52.7

0.00000

35

40

Unusual sensory interest

1.65

47.3

35.2

0.00000

38

28

Sensory hyperreactivity

8.55

39.4

47.3

0.00019

33

38

Sensory hyporeactivity

1.75

44.5

51.2

0.00042

36

39

Temper tantrums

2.35

48.2

39.6

0.00000

38

32

Aggression toward self

2.65

51.4

43.3

0.00000

40

36

Aggression toward others

2.15

50.8

41.9

0.00000

41

34

Loss of skills

5.15

39.8

47.5

0.00011

35

38

Loss of language (words only)

5.8

34.8

49.3

0.00000

30

39

Loss of language (phrases)

7.25

35.7

48.0

0.00000

32

38

Difficulty initating on maintaing relationships

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

Unusual interest in objects or toys

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

Less social engagement

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

Loss of motor skills

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

Loss of daily living skills

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”

“n.a.”