Sunday, December 18, 2022

The great decline in adolescent risk behaviours, 1999—2019: Unitary trend, separate trends, or cascade?

The great decline in adolescent risk behaviours: Unitary trend, separate trends, or cascade? Jude Ball et al. Social Science & Medicine, December 16 2022, 115616. https://doi.org/10.1016/j.socscimed.2022.115616

Abstract: In many high-income countries, the proportion of adolescents who smoke, drink, or engage in other risk behaviours has declined markedly over the past 25 years. We illustrate this behavioural shift by collating and presenting previously published data (1990–2019) on smoking, alcohol use, cannabis use, early sexual initiation and juvenile crime in Australia, England, the Netherlands, New Zealand, and the USA, also providing European averages where comparable data are available. Then we explore empirical evidence for and against hypothesised causes of these declines. Specifically, we explore whether the declines across risk behaviours can be considered 1) a ‘unitary trend’ caused by common underlying drivers; 2) separate trends with behaviour-specific causes; or 3) the result of a ‘cascade’ effect, with declines in one risk behaviour causing declines in others. We find the unitary trend hypothesis has theoretical and empirical support, and there is international evidence that decreasing unstructured face-to-face time with friends is a common underlying driver. Additionally, evidence suggests that behaviour-specific factors have played a role in the decline of tobacco smoking (e.g. decreasing adolescent approval of smoking, increasing strength of tobacco control policies) and drinking (e.g. more restrictive parental rules and attitudes toward adolescent drinking, decreasing ease of access to alcohol). Finally, declining tobacco and alcohol use may have suppressed adolescent cannabis use (and perhaps other risk behaviours), but evidence for such a cascade is equivocal. We conclude that the causal factors behind the great decline in adolescent risk behaviours are multiple. While broad contextual changes appear to have reduced the opportunities for risk behaviours in general, behaviour-specific factors have also played an important role in smoking and drinking declines, and ‘knock-on’ effect from these behavioural domains to others are possible. Many hypothesised explanations remain to be tested empirically.

Introduction

Throughout much of the developed world, adolescent smoking, drinking, underage sex, and juvenile crime declined dramatically between the late 1990s and around 2015 (Ball et al., 2018; Pape et al., 2018; Twenge, 2017), yet the reasons for this widespread and long-term trend are not well understood. Better understanding of what caused declines in risk behaviours is vital if we are to predict and influence future trends. Trends for some risk behaviours plateaued or even began to reverse in some countries in the 2015–2019 period, adding urgency to the need to understand what drives teen trends and apply the lessons to preventive efforts.

In this narrative review we document this shift in adolescent behaviour and discuss evidence to date on possible causes. Potential causes are explored within three overarching hypotheses which are not mutually exclusive: 1) declines represent a ‘unitary trend’ with common underlying causes resulting in simultaneous declines in many risk behaviours; 2) declines in various risk behaviours are separate, caused by behaviour-specific factors; and 3) declines in certain risk behaviours have caused declines in others (the ‘cascade’ hypothesis).

To contextualise the changes in risk behaviours it is important to consider how the lives of adolescents have changed over recent decades within the economic, social, cultural and technological spaces they inhabit. Contextual changes over time in the labour market, regulatory environment, school environment, parenting norms, youth culture, and information technology, for example, have undoubtedly shaped the experiences of young people as well as their worldviews, attitudes and behaviours. The idea that young people's development and behaviour are influenced by the contexts in which they grow up has been termed the social ecological approach (Brofenbrenner, 1977; Sallis et al., 2008). This approach provides an overarching theoretical framework within which we explore the recent shift in adolescent behaviour and possible causes.

This review has two parts. In the first, we present an overview of recent international trends in substance use, sexual behaviour and juvenile crime, highlighting long-term changes. In the second we discuss the plausibility of selected causal hypotheses for the simultaneous decline in multiple risk behaviours, drawing on theory and empirical evidence to date.

No comments:

Post a Comment