Table 2.
Number of samples (N), number of positive samples (n), proportion of positive samples (% pos) per Group (A, B) and year (2019, 2020), and p values (CWS = Cold Water System; HWS = Hot Water System).
| Group A | Group B | CWS | HWS | TOTAL | CWS | HWS | TOTAL | N/n (% pos) | N/n (% pos) | N/n (% pos) | N/n (% pos) | N/n (% pos) | N/n (% pos) | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2019 | 55/2 (3.6) | 135/21 (15.6) | 190/23 (19.2) | 75/2 (2.7) | 149/10 (6.7) | 224/12 (9.4) | ||||||||||||
| 2020 | 59/5 (8.5) | 42/19 (13.4) | 201/24 (21.9) | 85/1 (1.2) | 150/21 (14.0) | 235/22 (15.2) | ||||||||||||
| p | 0.102 | 0.172 | 0.30 | 0.110 | 0.038 | 0.302 | ||||||||||||