Cumulative Risk and Cumulative Protection: Relative Contributions to Predicting Substance Use, Antisocial Behaviour and Mental Health Across Development

BACKGROUND: Cumulative risk scores predict negative outcomes including antisocial behaviour and mental health. Less work has examined the role of cumulative protection, despite the availability of preventive interventions focused on bolstering protection across domains. Understanding links between cumulative risk and protection measured in childhood and later outcomes can help to guide the timing of prevention programmes. AIMS: The study aimed to understand the relative contributions of early adolescent cumulative risk and cumulative protection in Grade 6 on distal outcomes six to seven years later, at ages 18-19. METHODS: Data are from the Community Youth Development Study, a community-randomised trial of the Communities That Care prevention system. The analysis sample consisted of 2002 participants from 12 control communities. Logistic regression models were estimated to quantify the main and interactive effects of Grade 6 cumulative risk and protection on alcohol, tobacco and cannabis use; antisocial behaviour, and depression at ages 18-19. RESULTS: When considered in separate models, cumulative risk and protection were each associated with later alcohol, tobacco and cannabis misuse; antisocial behaviour and depression. When considered together, coefficients for cumulative protection were attenuated, whereas coefficients for cumulative risk remained similar in magnitude. Cumulative risk was associated with larger outcome prevalence differences (average of 9%) than cumulative protection (average of 2%). Evidence for risk-protection interactions was not observed. CONCLUSIONS: Although early adolescent cumulative protection was associated with later outcomes, these associations were largely reduced when considering cumulative risk. Findings emphasise the importance of addressing cumulative risk when designing preventive interventions.