Functional and quality of life outcomes after partial glossectomy: a multi-institutional longitudinal study of the head and neck research network

Table 2 Mixed effects linear regression models for Speech Handicap Index (SHI)

Subscale (n)	Variable	Estimate	95% CI	SE	t	p	SDs of Random Effects
Subscale (n)	Variable	Estimate	95% CI	SE	t	p	Intercept	Residual
SHI (n = 83)	Baseline	20.86	15.6 to 26.2	2.71	7.69		16.86	16.14
	1 month	+9.98	+3.7 to +16.2	3.14	3.18	.002*
	6 month	+9.24	+2.6 to +15.9	3.34	2.77	.006
	1 year	+7.66	+.4 to +14.8	3.69	2.08	.040
Psychosocial (n = 92)	Baseline	8.46	5.8 to 11.0	1.32	6.41		8.70	7.93
	1 month	+4.31	+1.2 to +7.4	1.55	2.79	.006
	6 month	+4.12	+.9 to +7.3	1.65	2.50	.013
	1 year	+4.04	+.5 to +7.6	1.80	2.25	.026
Speech (n = 92)	Baseline	11.55	9.2 to 13.9	1.21	9.55		7.60	7.75
	1 month	+5.41	+2.7 to +8.1	1.36	3.96	<.001*
	6 month	+4.65	+1.8 to +7.5	1.45	3.22	.002*
	1 year	+3.16	0 to +6.3	1.58	2.00	.048

Note.*p < .0028; Baseline = pre-operative estimate of mean subscale scores for combined cohort; 1 month/6 months/1 year = difference between combined cohort mean subscale scores and baseline mean for the respective assessment time point; p-value for baseline scores not provided given that it tests the hypothesis that the baseline mean is significantly different from 0, results of which are not meaningful; 95% CI calculated using bootstrapping