Table 3 Early skills achievement II

Motor

 Roll over

9

4–18

7.7 ± 4.6 months

6.0 (5.0–8.0) months

6 months

 Sit without support

10

6–13

8.2 ± 2.4 months

7.5 (7.0–8.0) months

9 months

 Crawl

9

8–16

10.9 ± 2.8 months

10.0 (9.0–13.0) months

n/a

 Take independent steps

10

12–22

16.5 ± 3.5 months

16.3 (13.3–19.5) months

15 months

Language

 Babble

9

6–36

13.0 ± 9.8 months

9.0 (8.0–10.0) months

9 months

 Single words

9

14–42

2.4 ± 1.0 years

2.0 (1.5–3.3) years

15–18 months

 Two-word phrases

8

30–62

3.8 ± 1.1 years

3.8 (2.9–4.8) years

24 months

 Fluent speech

7

48–96

5.7 ± 1.4 years

5.5 (4.8–6.5) years

36–48 months

Toileting

 Bladder control

7

36–288

7.5 ± 7.7 years

4.0 (3.7-7.0) years

∼ 36 months*

 Bowel control

7

36–120

4.8 ± 2.5 years

4.0 (3.4-5.0) years