| No need to test | 2 % |
| Only if they have a headache | 9 % |
| Over 50 years of age | 1 % |
| Used 2 or more air bottles | 17 % |
| Should test everyone | 70 % |
| Total | 1528 |
| No need to test | 2 % |
| Only if they have a headache | 9 % |
| Over 50 years of age | 1 % |
| Used 2 or more air bottles | 17 % |
| Should test everyone | 70 % |
| Total | 1528 |