One can test roughly with this test if (youth room? ...) Can be found traces of drug use in a given environment. This can be quite handy for parents who have a little suspicion and wish to exclude once that the children have to do with drugs. Because the first investigation without the assistance of the children is doable, it does not come to an early distrust expression and no confrontation. Parents can decide how they want to proceed after the test still. I think therefore this test more meaningful and better than the other, I also tested.