. Author manuscript; available in PMC: 2010 Jan 1.

Published in final edited form as: Infant Behav Dev. 2008 Oct 31;32(1):33–43. doi: 10.1016/j.infbeh.2008.09.007

Table 4.

Descriptive statistics at each age for Study 2.

Measure	Age (n = 60)
	9 Months			12 Months			30 Months
	M	SD	No.	M	SD	No.	M	SD	No.
Rate of IJA Episodes^a	8.15	4.96	59	8.06	4.37	60
Anticipatory Smiling	0.17	0.21	40	0.25	0.19	51
Reactive Smiling	0.14	0.14	41	0.13	0.13	43
ITSEA-Competence^b							49.49	10.18	39
ITSEA-Externalizing^b							44.87	07.54	39
ITSEA-Internalizing^b							49.44	07.33	39
ITSEA-Dysregulation^b							49.49	10.18	39

Note. No. = number of infants who displayed behaviors at least once; IJA = initiating joint attention; Anticipatory Smiling = proportion of IJA episodes involving anticipatory smiles; Reactive Smiling = proportion of IJA episodes involving reactive smiles.

Rate is per 10 min.

Values reflect T-scores with a mean of 50 and a standard deviation of 10.