Table 2. OS based on sociodemographic and clinical characteristics.

S. no	Status	Number	1 year (%)	3 years (%)	5 years (%)	p value
	OS	1,895	86	73	65
1.	Age (in years)					0.36
	<40	535	87	72	69
	41–60	1,043	85	72	65
	>60	317	88	75	60
2.	Gender					0.89
	Male	1,549	86	73	65
	Female	346	87	73	66
3.	Primary site (ICD-10)					0.55
	Tongue (C02.9)	697	88	73	67
	Gum and alveolus (C03.9)	246	84	73	61
	Mouth (04.9)	180	90	73	65
	Hard palate (05.0)	39	78	66	62
	Buccal mucosa (C06.0)	675	84	72	66
	Retromolar area (C06.2)	51	88	69	47
4.	Histology grade					<0.001
	Well-differentiated	226	93	85	79
	Moderately differentiated	860	89	74	65
	Poorly-differentiated	263	85	66	58
	Undifferentiated	546	78	62	55
5.	TNM stage					<0.001
	Stage I	213	98	89	83
	Stage II	262	90	87	80
	Stage III	241	91	76	70
	Stage IV	951	82	65	55
6.	Intent of treatment					<0.001
	Curative	1,756	88	75	68
	Palliative	139	52	16	11
7.	Treatment completion					<0.001
	Complete treatment	1,658	88	75	67
	Partial treatment	237	71	48	43
8.	Treatment type					<0.001
	Surgery	534	95	79	74
	Radiotherapy	68	72	62	58
	Chemotherapy	258	51	22	7
	Surgery + radiotherapy	469	94	86	78
	Chemo + radiotherapy	95	72	47	38
	Surgery + chemotherapy	20	70	56	21
	Surgery + chemo + radiotherapy	451	89	73	64