The Montreal Longitudinal and Experimental Study: The Intervention Program and its Long Term Effects
"The Montreal Longitudinal-Experimental Study (McCord et al, 1994; Tremblay et al., 1995), a preventive intervention, offered a parent training program to the parents (...) Because a social skills program was also offered to the children at school, this study could not assess the specific effects of the parent training program. However, the combined programs showed significant positive effects on self-reported delinquent behaviour up to seven years after the end of the intervention, when boys were 15 years old." (p.119)
National Research Council Institute of Medicine. (2001). Preventing Juvenile crime. In J. McCord, C. Spatz Widom, & N. A. Crowell (Eds.) Juvenile crime, juvenile justice. National Academy Press.