Table 1. Descriptive statistics of the 2 skin reactions to the tuberculin skin test obtained during the contact investigation by exposure group.
| Exposure group* |
Number of subjects† |
Erythema | Induration | ||
| Mean (mm) | Standard deviation (mm) | Mean (mm) | Standard deviation (mm) | ||
| 1 | 28 | 52.9 | 16.3 | 23.3 | 3.9 |
| 2 | 67 | 49.5 | 27.8 | 20.1 | 7.0 |
| 3 | 97 | 39.8 | 22.8 | 17.4 | 7.4 |
| 4 | 351 | 28.1 | 15.9 | 15.8 | 5.1 |
| All | 543 | 34.1 | 21.0 | 17.0 | 6.1 |
* : Group 1, homeroom classmates; Group 2, students who shared special classes or extracurricular activities with the case; Group 3, third-grade students after excluding those who belonged to exposure group 1 and group 2; Group 4, first- or second-grade students after excluding those who belonged to exposure group 2.
† : Students who had the tuberculin skin test administered by the public health center are used.