. Author manuscript; available in PMC: 2015 Oct 1.

Published in final edited form as: J Exp Child Psychol. 2014 May 27;126:37–51. doi: 10.1016/j.jecp.2014.02.012

Table 2.

Descriptive statistics for the measures used in both years of the study

		Mean	Std. Dev.	Max	Min	Percentiles
						75^th	50^th	25^th
Year 1 – Age 3	TOSA	0.12	1.01	2.49	−1.69	0.66	0.16	−0.59
	PPVT Raw	71.50	20.29	131.00	35.00	84.25	70.50	57.00
	PPVT Percentile	71.89	27.09	99.90	16.00	95.25	78.00	53.75
Year 2 – Age 4	FIST	24.70	3.96	30.00	14.00	28.00	25.00	22.00
	Tap Test	11.82	4.68	16.00	0.00	15.75	13.00	10.00
	VMI	11.23	3.09	20.00	1.00	13.00	11.00	9.25
	WIAT	19.09	5.21	30.00	9.00	23.75	18.00	15.25

Notes: TOSA = Test of Spatial Assembly (average of z-scores from 2-D and 3-D portions of the test); PPVT = Peabody Picture Vocabulary Test; FIST = Flexible Item Selection Task; VMI = Beery Test of Visual-Motor Integration; WIAT = Wechsler Individual Achievement Test– Math Problem Solving subtest.