Table 3 The proportion of individuals with the CDKL5 disorder of a particular current age who had attained various gross motor, communication and hand milestones

Gross motor

Roll front to back

4 (36.4)

1 (100)

46 (92)

5 (50)

27 (84)

2 (40)

14 (88)

1 (50)

Roll back to front

5 (45)

1 (100)

47 (94)

5 (50)

26 (81)

2 (40)

14 (88)

1 (50)

Transition from sitting to crawling position

1 (9)

1 (100)

23 (46)

3 (30)

16 (50)

0 (0)

5 (31)

1 (50)

Crawl

1 (9)

0 (0)

12 (24)

2 (20)

10 (31)

0 (0)

4 (25)

1 (50)

Stand with support

2 (18)

1 (100)

37 (74)

3 (30)

22 (69)

1 (20)

10 (63)

1 (50)

Pull to stand

1 (9)

0 (0)

13 (26)

2 (20)

14 (44)

1 (20)

6 (38)

1 (50)

Walk with support

1 (9)

0 (0)

24 (48)

1 (10)

16 (50)

1 (20)

8 (50)

1 (50)

Fine motor

Transfer from hand to hand

3 (27)

1 (100)

25 (50)

2 (20)

18 (56)

0 (0)

8 (50)

0 (0)

Play with blocks

0 (0)

0 (0)

8 (16)

1 (10)

8 (25)

0 (0)

2 (13)

0 (0)

Social and communication

Social smile

8 (73)

1 (100)

38 (76)

7 (70)

18 (56)

1 (20)

9 (56)

0 (0)^a

Fix and follow

3 (30.0)^a

1 (100)

39 (78)

4 (40)

23 (72)

1 (20)

10 (67)^a

1 (100)^a

Wave goodbye

0 (0.0)

0 (0)

11 (22)

1 (10)

4 (13)

0 (0)

1 (6)

0 (0)

Respond to own name

4 (36)

1 (100)

33 (66)

3 (33.3)^a

20 (63)

2 (40)

9 (56)

0 (0)

Point to things that he/she wants

0 (0.0)

0 (0)

6 (12)

1 (10)

8 (26)^a

0 (0)

2 (13)

0 (0)

Respond to others emotions

4 (36)

1 (100)

23 (47)^a

4 (40)

11 (34)

1 (20)

4 (25)

1 (50)

Respond to ‘no’

2 (18)

0 (0)

16 (32)

2 (25)^a

13 (41)

0 (0)

4 (25)

0 (0)

Phrases

0 (0.0)

0 (0)

3 (6)

0 (0)

3 (9)

0 (0)

1 (6)

0 (0)