PART V (time to completion: 15 minutes)
Important data from the case-control study are shown in Table 2 below.
Exposures to buildings, Legionnaires' disease outbreak, Louisiana, 1989
| Cases Exposed/Total (%) | Controls Exposed/Total (%) | Odds Ratio | P-value | |
| Indoor exposure to buildings with cooling towers | ||||
| Retail Store A | 3/28 (11%) | 10/54 (19%) | 0.5 | 0.5 |
| Post Office | 7/27 (26%) | 12/50 (24%) | 1.1 | 0.9 |
| Hospital A | 5/28 (18%) | 12/54 (22%) | 0.8 | 0.9 |
| Hospital B | 3/28 (11%) | 7/56 (13%) | 0.8 | 1.0 |
| Paper Mill | 2/28 (7%) | 4/56 (7%) | 1.0 | 1.0 |
| Outdoor exposure to stores near paper mill cooling towers | ||||
| Retail Store A | 3/28 (11%) | 10/54 (19%) | 0.5 | 0.5 |
| Retail Store B | 10/28 (36%) | 15/52 (29%) | 1.4 | 0.7 |
| Retail Store D | 5/28 (18%) | 7/54 (13%) | 1.5 | 0.5 |
| Retail Store E | 6/28 (21%) | 9/54 (17%) | 1.4 | 0.8 |
| Restaurant A | 2/26 (8%) | 5/52 (10%) | 0.8 | 1.0 |
| Bank A | 11/28 (39%) | 19/53 (36%) | 1.2 | 0.9 |
| Butcher Store A | 12/27 (44%) | 10/54 (19%) | 3.5 | 0.03 |
| Any of the above | 19/28 (68%) | 33/56 (59%) | 1.5 | 0.6 |
| Outdoor exposure to stores near other large cooling towers | ||||
| Drug Store A | 7/28 (25%) | 15/55 (27%) | 0.9 | 1.0 |
| Drug Store B | 13/28 (46%) | 20/54 (37%) | 1.5 | 0.6 |
| Doctors Plaza A | 2/27 (7%) | 8/56 (14%) | 0.5 | 0.5 |
| Retail Store F | 4/28 (14%) | 6/54 (11%) | 1.3 | 0.7 |
| Exposure to stores frequently reported by case-patients | ||||
| Grocery Store A | 25/27 (93%) | 28/54 (52%) | 11.6 | <0.01 |
| Grocery Store B | 19/28 (68%) | 23/54 (43%) | 2.9 | 0.05 |
| Retail Store C | 22/28 (79%) | 30/54 (56%) | 2.9 | 0.07 |