Although studies conducted by questionnaire are sometimes suspect, Kandel's1 evaluation of peer and parent influence on marihuana use by adolescents seems above reproach. Questionnaires were given in a random sample of homerooms in 13 high schools and to the entire student body in five other schools in New York State. Later a questionnaire was mailed to one parent of each student, alternately mothers and fathers. It was possible to match 49% of all the students to parents and 38% of the students in the five schools to their best school friends. In these five schools, 23% of students could be matched to parents as well as to their best school friends.
Students were asked about their use of marihuana and about their perception of parents' use of psychoactive drugs. Parents were also asked about their own use of such drugs. There appeared a tendency for students to use marihuana
Hussey HH. Marihuana Use by Adolescents. JAMA. 1973;226(6):661-662. doi:10.1001/jama.1973.03230060039013