Table 3.

Hurdle models for the Spanish samples examining predictors of the odds of engaging in any between-utterance and within-utterance code-switching (CS; top) and the frequency of such CS among those children who switch at least once (bottom).

Variable	Between-utterance CS to English				Within-utterance CS to English
	Estimate	SE	χ2	p	Estimate	SE	χ2	p
	Logistic model of odds of engaging in CS
Observations	n = 66 (33 DLD, 33 TLD)				n = 66 (33 DLD, 33 TLD)
Intercept	−2.20	0.76			0.67	0.40
Age in months (centered)	−0.23	0.09	10.22	.001	−0.02	0.03	0.35	.555
Spanish BESA (group z score)	−1.24	0.60	5.49	.019	−0.49	0.29	3.06	.080
Group (DLD vs. TLD)	−1.85	1.20	3.26	.071	−0.80	0.59	1.89	.170
English BESA (group z score)	0.36	0.48	0.58	.447	0.40	0.29	2.08	.149
Spanish BESA x Group	3.28	1.27	9.49	.002	Adding an interaction term does not improve the model (χ2 = 0.79, p = .37)
Negative binomial count model of CS utterances (out of total utterances) given at least one CS utterance
Observations	n = 12 (10 DLD, two TLD)				n = 37 (22 DLD, 15 TLD)
Intercept	n/a (too few observations)				−2.61	0.32
Age in months (centered)					−0.05	0.02	4.46	.035
Spanish BESA (group z score)					−0.76	0.26	7.81	.005
Group (DLD vs. TLD)					−0.34	0.43	0.59	.441
English BESA (group z score)					0.05	0.27	0.03	.859
Spanish BESA x Group					Adding an interaction term does not improve the model (χ2 = 0.44, p = .51)

Note. Bold values indicate significant effects based on a likelihood ratio test. To measure proficiency while reducing the confound with diagnostic status, Spanish and English Bilingual English-Spanish Assessment (BESA) morphosyntax standard scores were z scored within each group separately. Coefficients indicate the effect of a 1 SD increase above the mean score within the child's group. DLD = developmental language disorder; TLD = typical language development; n/a = not applicable.