Table 2.

Means and Standard Deviations for Measures of Speech Disfluency, Age, SES (Social-economic Status), Speech-language, and Behavioral Inhibition for All Preschool-age Participants (CWS+CWNS), CWS and CWNS.

	All (N=54)		CWS (N=26)		CWNS (N=28)		Sig. Δ (CWS vs.CWNS)	Effect sizes
	M	SD	M	SD	M	SD
Speech disfluency
Total disfluencies / 100words	8.46	6.32	13.53	5.31	3.76	2.14	p<.01*	d=2.45
Stuttered disfluencies / 100words	5.44	5.54	9.97	4.84	1.22	.56	p<.01*	d =2.59
Non-stuttered disfluencies/100words	3.02	2.36	3.55	2.71	2.54	1.91	p=.138	d =0.43
SSI total	13.37	7.66	20.31	5.09	6.93	1.39	p<.01*	d =3.65
Individual differences
Age	47.89	7.45	48.89	8.00	46.96	6.93	p=.349	d =0.26
SES	44.56	12.96	42.08	13.68	47.04	11.93	p=.170	d =−0.39
Speech language
PPVT standard score	114	10.90	113.08	10.82	115.96	10.99	p=.336	d =−0.263
EVT standard score	118.09	11.07	113.73	9.51	122.14	11.02	p=.004*	d =−0.82
TELD-R standard score	122.61	11.02	119.04	12.12	125.93	8.85	p=.020*	d =−0.65
TELD-E standard score	113.20	12.43	110.85	15.53	115.39	8.36	p=.182	d =−0.37
GFTA standard score	121.48	11.54	109.69	8.42	112.11	10.74	p=.365	d =−0.25
MLU	4.76	.93	4.85	1.17	4.68	.65	p=.955	d =0.18
Behavioral inhibition (BI)
BI (latency to the 6th SC in seconds)	204.94	203.46	257.15	268.67	156.37	111.41	p=.165	η2 = 0.040

^*=significant at 0.05 level of confidence.