| Value |
Category |
| -9 |
-9. Don't know |
| 1 |
1. Totally useless |
| 2 |
2. Hardly ever works |
| 3 |
3. Sometimes works |
| 5 |
5. Very effective |
Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.