1. Different questions were used each time an interview took place
1 of 20
Other questions in this quiz
2. The number of non users had...
- Not changed
3. 106 participants had...
- stopped using cocaine by the end of the study
- increased their heroin intake by the end of the study
4. The addicts became more truthful about their cocaine use over the course of the study
5. What was their mean age?