Policy-makers are considering large-scale programs aimed at self-control to improve citizens’ health and wealth and reduce crime. Experimental and economic studies suggest such programs could reap benefits. Yet, is self-control important for the health, wealth, and public safety of the population? Following a cohort of 1,000 children from birth to the age of 32 y, we show that childhood self-control predicts physical health, substance dependence, personal finances, and criminal offending outcomes, following a gradient of self-control. Effects of children's self-control could be disentangled from their intelligence and social class as well as from mistakes they made as adolescents. In another cohort of 500 sibling-pairs, the sibling with lower self-control had poorer outcomes, despite shared family background. Interventions addressing self-control might reduce a panoply of societal costs, save taxpayers money, and promote prosperity.

Bullying victimization is a topic of concern for youths, parents, school staff and mental health practitioners. Children and adolescents who are victimized by bullies show signs of distress and adjustment problems. However, it is not clear whether bullying is the source of these difficulties. This paper reviews empirical evidence to determine whether bullying victimization is a significant risk factor for psychopathology and should be the target of intervention and prevention strategies. Research indicates that being the victim of bullying (1) is not a random event and can be predicted by individual characteristics and family factors; (2) can be stable across ages; (3) is associated with severe symptoms of mental health problems, including self-harm, violent behaviour and psychotic symptoms; (4) has long-lasting effects that can persist until late adolescence; and (5) contributes independently to children's mental health problems. This body of evidence suggests that efforts aimed at reducing bullying victimization in childhood and adolescence should be strongly supported. In addition, research on explanatory mechanisms involved in the development of mental health problems in bullied youths is needed.

Background: Controversy remains as to whether cannabis acts as a causal risk factor for schizophrenia or other functional psychotic illnesses.Aims: To examine critically the evidence that cannabis causes psychosis using established criteria of causality.Method: We identified five studies that included a well-defined sample drawn from population-based registers or cohorts and used prospective measures of cannabis use and adult psychosis.Results: On an individual level, cannabis use confers an overall twofold increase in the relative risk for later schizophrenia. At the population level, elimination of cannabis use would reduce the incidence of schizophrenia by approximately 8%, assuming a causal relationship. Cannabis use appears to be neither a sufficient nor a necessary cause for psychosis. It is a component cause, part of a complex constellation of factors leading to psychosis.Conclusions: Cases of psychotic disorder could be prevented by discouraging cannabis use among vulnerable youths. Research is needed to understand the mechanisms by which cannabis causes psychosis.