Three Generational Study (3GS)

Based on Research Conducted at OSLC

A study focused on the intergenerational transmission of alcohol, tobacco, and other drug use, including marijuana use, across three generations, and effects of state recreational marijuana legalization on adolescents’ use.

Project Overview

The original Oregon Youth Study began 1983. The goal was to examine the etiology of antisocial behaviors in boys, with a view to designing preventive interventions within the context of the family and the school. This longitudinal study has expanded over the past few decades into an intergenerational study, retaining the original young men and including their partners and children.

Intergenerational studies are critical to informing research, preventive intervention, and policy regarding family influences on healthy development and maladjustment. Continuities in family socialization and contextual risks across generations, as well as genetic factors, are associated with the development of psychopathology – including both conduct problems and depressive symptoms in children – and with intergenerational associations in the use of alcohol, tobacco, and other substances. As a parent shares on average 50% of their genes with a biological child, accurate estimates of the magnitude of intergenerational associations in these problem behaviors are needed in order to identify contributing factors that could be targets of intervention. The size of the associations places an upper bound on the contribution of all continuity factors combined, including genetic contributions. If the magnitude of associations is small, then genetic and environmental continuities may not be as strong as has often been assumed or may be subject to considerable moderation.

Given the importance of intergenerational studies, it is perhaps surprising to note that, until relatively recently, such studies tended to be based on the retrospective reports of one generation about both their own behavior and that of the prior generation.

In the current 5-year period which began in 2018, the intergenerational study has expanded to be an Intergenerational Research Consortium which involves a collaboration with two other research groups and studies. Intergenerational questions will be addressed using 35 years of data and 3 generations from the Oregon Youth Study, and similar data from the Seattle Social Development and Intergenerational Projects (Dr. Jennifer Bailey), and the Rochester Youth Development and Intergenerational Studies (Dr. Kim Henry).

The study will focus on the intergenerational transmission of alcohol, tobacco, and other drug use, including marijuana use, across three generations, and effects of state recreational marijuana legalization on adolescents’ use. We will use a strategy of (1) intensive study of the long-term Oregon Youth Study data set; (2) replications across the three studies through collaborations with the other consortium research teams, and (3) integrative data analysis across these three studies on up to 1,200 G3 children of diverse socioeconomic, regional, and racial/ethnic backgrounds.

Year Project Began: 1998
Funder: National Institute on Drug Abuse

Principal Investigator

Deborah Capaldi, Ph.D.

Senior Research Scientist
Oregon Social Learning Center

Active Research Projects

Primary Research and Clinical Interests

Primary research interests include: individual, social and contextual influences on the development of psychopathology and substance use from childhood through adulthood, particularly intergenerational influences on risk and substance use; life-span antisocial and associated behaviors, including early childhood risk, child and adolescent development, delinquent and criminal behavior, health-risking sexual behavior, use of alcohol and other substances, violence, depression, and fatherhood; and adjustment of couples, including interaction patterns and aggression, stress, and effects of relationship factors on health. Additional interests include longitudinal developmental modeling and study design, and observational assessment techniques.