Non-Response | Numbers of subjects responding | Attack rates | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
%(n) | %(n) | Exposed | Not exposed | Exposed | Risk ratio | 95% CI# | ||||
Cases | Total | Cases | Total | Cases | Total | Yes | No | |||
Drink | ||||||||||
DDWD* | 0 | 0 | 41 | 162 | 13 | 153 | 25 | 8.5 | 3.0 | 1.7 ~ 5.3 |
Bottled water | 0 | 0 | 1 | 6 | 53 | 309 | 17 | 1.7 | 0.97 | 0.16 ~ 5.9 |
Repast time in company | ||||||||||
Breakfast | 0.0(1) | 0.0(10) | 48 | 274 | 6 | 41 | 18 | 15 | 1.2 | 0.55 ~ 2.6 |
Lunch | 0 | 0.0(2) | 53 | 311 | 1 | 4 | 17 | 25 | 0.68 | 0.12 ~ 3.8 |
Supper | 0 | 0.0(5) | 52 | 306 | 2 | 9 | 17 | 22 | 0.77 | 0.22 ~ 2.7 |
Food taken late at night | 0.3(17) | 0.3(88) | 47 | 278 | 7 | 37 | 17 | 19 | 0.89 | 0.44 ~ 1.8 |
Contact with patients | 86(25) | 49(104) | 12 | 22 | 17 | 189 | 55 | 9.0 | 6.1 | 3.4 ~ 11 |
Eating raw and cold food | 0 | 0 | 13 | 47 | 38 | 236 | 28 | 16 | 1.7 | 1.0 ~ 3.0 |