Disentangling the relationship between delinquency and hyperactivity, low achievement, depression, and low socioeconomic status: Analysis of repeated longitudinal data

Abstract

Purpose

To test hypotheses about causal linkages among hyperactivity, low academic achievement, depression, low SES, and delinquency.

Methods

503 boys were followed up in the Pittsburgh Youth Study. Comparable measures of all variables at each age from 11 to 15 are analyzed. Cross-lagged panel models are tested.

Results

Hyperactivity, depression and achievement decreased with age, while SES and delinquency increased with age. The analyses suggest that hyperactivity and low SES caused low achievement, which in turn caused delinquency, which in turn caused depression.

Conclusions

Depression is not a risk factor for delinquency. These analyses should be repeated with larger numbers of variables. Developmental and life-course theories should propose and test sequential rather than simultaneous influences on offending. Since low achievement has the most direct influence on delinquency, interventions should target low achievement rather than hyperactivity or SES.

Introduction

Hyperactivity, low academic achievement, depression, and low socioeconomic status (SES) are viewed as important risk factors for delinquency (see e.g. Derzon, 2010, Farrington et al., 2012, Farrington et al., 1990, Loeber et al., 1998a, Loeber et al., 1998b). A risk factor is defined as a variable that precedes and predicts an outcome such as delinquency. A risk factor is considered to have causal effects if changes in the risk factor are followed by changes in the outcome with high internal validity (see, e.g., Murray, Farrington, & Eisner, 2009). Therefore, longitudinal research is needed to investigate risk factors and causal risk factors.

While the most important risk factors for delinquency have been well established for many years and are highly replicable across time and place (e.g., Farrington & Loeber, 1999), less is known about causal influences and intervening mechanisms. For example, if hyperactivity and low academic achievement both predict delinquency, is it that hyperactivity causes low academic achievement which in turn causes delinquency, so that hyperactivity only indirectly influences delinquency through the mediating factor of low academic achievement? Similarly, if low SES and low academic achievement both predict delinquency, is it that low SES causes low academic achievement which in turn causes delinquency, so that low SES only indirectly influences delinquency through the mediating factor of low academic achievement? The main aim of this paper is to investigate these alternative sequences of risk factors and mediating processes.

The relationship between depression and delinquency is particularly perplexing. Depression is positively related to delinquency (e.g., Loeber et al., 1998a, Loeber et al., 1998b). However, depression is classified as an internalizing problem and is positively related to other internalizing problems such as anxiety and shyness/withdrawal (Achenbach & Edelbrock, 1983). Nevertheless, anxiety and shyness/withdrawal are often negatively related to delinquency and are sometimes regarded as protective factors against delinquency. For example, in the Cambridge Study in Delinquent Development, which is a longitudinal survey of over 400 London boys, Farrington, Gallagher, Morley, St. Ledger, and West (1988) found that boys from criminogenic backgrounds who did not become offenders tended to have few or no friends at age 8. Similarly, Kerr, Tremblay, Pagani, and Vitaro (1997), in the Montreal longitudinal-experimental study of over 1,000 boys, concluded that behavioral inhibition (anxiety) protected boys against delinquency. The present paper aims to advance knowledge about the relationship between depression and delinquency.

There have been previous attempts to investigate causal effects and mediating mechanisms (see, e.g., Baron and Kenny, 1986, Hayes, 2009). For example, McGloin, Pratt, and Maahs (2004), using US National Longitudinal Survey of Youth data, concluded that the relationship between low intelligence and delinquency was mediated by low school achievement, low self-control, and deviant peer pressure. Masten et al. (2005), in a Minneapolis longitudinal study of over 200 children from age 8 to age 20, concluded that childhood externalizing behavior (aggression and delinquency) led to low academic achievement in adolescence, which in turn led to externalizing and internalizing problems later in life. The present study goes beyond previous research by including more risk factors and by analyzing comparable annually collected data in the Pittsburgh Youth Study (PYS; see later).

Annually collected data in the PYS was previously used to study causal effects by comparing within-individual analyses and between-individual analyses (Farrington, Loeber, Yin, & Anderson, 2002). The authors found that poor parental supervision predicted a boy's delinquency both between and within individuals, but that peer delinquency predicted a boy's delinquency between individuals but not within individuals. In other words, changes in peer delinquency within individuals (from one assessment to the next) did not predict subsequent changes in a boy's delinquency from one assessment to the next. This suggested that peer delinquency might not be a cause of a boy's delinquency but might instead be measuring the same underlying construct (perhaps reflecting co-offending). In contrast, poor parental supervision was predictive within individuals and therefore might be a causal factor. These kinds of analyses can only be carried out in a study such as the PYS with numerous comparable assessments repeated at regular intervals.

The present paper uses similar PYS data to investigate causal linkages between hyperactivity, low academic achievement, depression, low SES, and delinquency.

The following are plausible hypotheses which will be tested:

• Hyperactivity, low achievement, depression, and low SES cause delinquency

• Delinquency causes hyperactivity, low achievement, and depression. The hypothesis that delinquency of a boy causes low SES of his parents seems very unlikely and was not tested.

• Hyperactivity causes low achievement which in turn causes delinquency. The alternative hypothesis that low achievement causes hyperactivity which causes delinquency was also tested.

• Low achievement causes depression which in turn causes delinquency. The alternative hypothesis that depression causes low achievement which causes delinquency was also tested.

• Low SES causes hyperactivity, low achievement, and depression, which in turn cause delinquency.

These hypotheses were tested in cross-lagged panel models.