Table 3. Multivariable logistic regression coefficients and odds ratios for the NTCP models for patient-reported xerostomia 3 and 12 months after treatment.

	Predictive factors	β	p	Odds Ratio	95% CI
XER HNSCC-3m	(n = 3)
	Dmean-c	0.637	<0.001	1.892	1.724–2.075
	Dmean-i	0.185	<0.001	1.203	1.164–1.243
	Age	0.202	<0.001	1.223	1.159–1.291
	Constant	−32.296	<0.001
XER HNSCC-12m	(n = 3)
	Dmean-c	1.400	<0.001	4.054	3.287–5
	Dmean-i	0.358	<0.001	1.43	1.33–1.539
	T stage
	T0	0.622	0.182	1.862	0.747–4.64
	T1	−1.136	<0.001	0.321	0.184–0.562
	T2	−19.544	0.99	0	0
	T3	0	<0.001	0
	Constant	−44.877	<0.001
XER NPC-3m	(n = 4 )
	Dmean-c	0.218	<0.001	1.244	1.195–1.295
	Dmean-i	0.185	<0.001	1.203	1.157–1.251
	Financial status
	f0	21.754	0.028	2.889
	f1	21.316	0.998	1.889
	f2	42.23	0.998	2.218
	f3	0	0.997
	Age	0.158	0	1.171	1.124–1.22
	Constant	−44.98	<0.001
XER NPC-12m	(n = 3)
	Dmean-c	0.558	<0.001	1.747	1.613–1.893
	Dmean-i	0.538	<0.001	1.712	1.585–1.85
	Education
	E0	0	<0.001	0
	E1	1.228	0.009	3.413	1.367–8.526
	E2	2.198	<0.001	9.011	3.543–22.919
	Constant	−45.962	<0.001	0

Abbreviation: Dmean-c: the mean dose given to the contralateral parotid gland; Dmean-i: the mean dose given to the ipsilateral parotid gland; SIB: simultaneous integrated boost; SQM: sequential mode; HNSCC: head and neck squamous cell carcinoma; NPC: nasopharyngeal carcinoma; LASSO: least absolute shrinkage and selection operator; XER: Xerostomia; XER3m or 12m: patient-reported moderate- to-severe xerostomia after 3- or 12-month.