| Value | Category | Cases | |
|---|---|---|---|
| 1 | Yes, it is essential | 664 |
65.3%
|
| 2 | Yes, but not essential | 149 |
14.7%
|
| 3 | No, it is not useful | 80 |
7.9%
|
| 4 | Other | 124 |
12.2%
|
| Sysmiss | 464 |