Table 1

Characteristics	Group 2^a N (%)	Group 3^b N (%)
Ever used mouthwash
No	12 (16.44)	10 (38.46)
Yes	61 (83.56)	16 (61.54)
Current use of mouthwash
Never used	12 (16.44)	10 (38.46)
Used in the past	16 (21.92)	5 (19.23)
Current use/1 year ago	45 (61.64)^c	11 (42.31)^d
Years of using mouthwash
≤ 5 years	20 (58.82)	1 (14.29)
6 - 15 years	8 (23.53)	3 (42.86)
16 - 25 years	3 (8.82)	2 (28.57)
25 years	3 (8.82)	1 (14.29)
Missing	11	4
Frequency of use
< Once/week	11 (24.44)	3 (27.27)
Once or twice/week	7 (15.56)	2 (18.18)
Every other day	4 (8.89)	1 (9.09)
Once/day	12 (26.67)	2 (18.18)
Twice/day	11 (24.44)	2 (18.18)
Three times/day	-	1 (9.09)
Time interval between brushing teeth and use of mouthwash
< 1 min	29 (64.44)	6 (54.55)
About 5 min	11 (24.44)	3 (27.27)
About 1 hour	2 (4.44)	-
About 2 hours	1 (2.22)	-
Other	2 (4.44)	2 (18.18)
Dilute mouthwash
No	42 (93.33)	9 (81.82)
Yes	3 (6.67)	2 (18.18)
Amount of mouthfuls
Only one	40 (88.89)	11 (100)
Two or more	5 (11.11)	-
Time kept in mouth
A few seconds (≤ 20 sec.)	19 (44.19)	6 (54.55)
Longer (> 20 sec.)	24 (55.81)	5 (45.45)
Missing	2	-
Swallow mouthwash
No	45 (100)	11 (100)
Yes	-	-
Mouthwash contains alcohol^e
No	21 (51.22)	3 (27.27)
Yes	25 (60.98)	8 (72.73)
Missing	4	-
Glasses of wine equivalent rinsed per year (users of alcohol containing mouthwash)
1 - 25	13 (52)	5 (62.5)
26 - 50	5 (20)	-
51 - 100	3 (12)	2 (25)
101 - 150	-	-
151 - 200	3 (12)	-
200	1 (4)	1 (12.5)
Years rinsed with one glass of wine equivalent per day (users of alcohol containing mouthwash)
0.0 - 0.4	13 (68.42)	2 (40)
0.5 - 0.9	2 (10.53)	-
1 - 1.9	2 (10.53)	2 (40)
2 - 2.9	-	1 (20)
3	2 (10.53)	-
Missing	6	3

^aGroup 2 are participants who filled in the mouthwash use questionnaire.
^bGroup 3 are controls of the Feasibility Head and Neck Cancer Study.
^cQuestionnaire asked for the current use of mouthwash.
^dGroup 3 was asked about mouthwash use one year ago.
^eNumbers do not add up to total, because 5 participants in the Mouthwash Use project used two different mouthwash brands.