Table 2.

Proportion of individuals in each category and mean (SD) of Restraint, Bayley Scales, and Free Play and the mean (SD) of Toy Removal at each age.

	14 Months	20 Months	24 Months
RESTRAINT
0	0.08	0.18	0.33
1	0.12	0.10	0.15
2	0.12	0.10	0.13
3	0.18	0.15	0.10
4	0.26	0.19	0.16
5	0.14	0.12	0.08
6	0.10	0.16	0.06
Mean (SD)	2.92 (0.62)	2.80 (0.78)	2.43 (0.78)
TOY REMOVAL
Mean (SD)	2.41 (0.51)	2.37 (0.54)	2.22 (0.37)
BAYLEY SCALES
0	0.18	0.36	0.52
1	0.54	0.48	0.42
2	0.28	0.16	0.07
Mean (SD)	1.38 (0.41)	1.24 (0.37)	1.13 (0.26)
FREE PLAY
0	0.22	0.08	0.12
1	0.61	0.68	0.71
2	0.18	0.25	0.17
Mean (SD)	1.28 (0.38)	1.33 (0.34)	1.28 (0.30)

SD, standard deviation.