Cohort Profile: The Zurich Project on the Social Development from Childhood to Adulthood (z-proso)

The Zurich Project on the Social Development from Childhood to Adulthood (z-proso) began in 2004 in response to the need for a better evidence base to support optimal child social development and prevent crime and violence. Since then, the study has tracked the development of a diverse sample of youths (N = 1,675 in the target sample; ~50% female) from age 7 (n = 1,360) to age 20 (n = 1,180), with primary data collection waves at ages 7, 8, 9, 10, 11, 12, 13, 15, 17, and 20. The study uses a multi-method, multi-informant design that combines teacher, youth, and parent reports with observational and behavioural measures, biosampling, functional imaging, and ecological momentary assessment. Analyses of the data have contributed important evidence to a diversity of topics in child and adolescent development, illuminating the developmental roots of crime and aggression, the impacts of exposure to different forms and combinations of victimisation, and trajectories of mental health and neurodevelopmental symptoms

The Role of Early Adolescence in Subsequent Risk and Resilience

Early adolescence comes with new opportunities for subsequent risk and resilience. Yet, international cohort studies covering this important developmental period and extending into young adulthood are rare. To address this gap in research, this special issue draws on data from the Zurich Project on Social Development from Childhood to Adulthood (z-proso). We outline the terminology for risk and resilience used in this special issue, describe the z-proso study design, characterize the z-proso sample in terms of important markers of adolescence, and provide an overview of Switzerland as a study setting. The contributions to this special issue highlight that adolescent well-being is not a given, even in a setting with relatively low contextual risk. Supportive parent–child relationships in early adolescence emerged as an important promotive factor for longer-term well-being. This special issue illustrates how early adolescence serves as an important juncture for different areas of future development

Developmental Trajectories of Self-, Other-, and Dual-Harm across Adolescence: The Role of Relationships with Peers and Teachers

Introduction: We investigated the longitudinal course of self-, other-, and dual-harm in adolescents, focusing on the infliction of physical injury on oneself, another person, or both parties, respectively. We examined the within-person transitions between these types of harm and whether relationships with peers and teachers predict individual harm trajectories. Methods: We used community-representative longitudinal data (N = 1,482; 52% male; 50% both parents born abroad). The participants self-reported self- and other-harm at 13, 15, 17, and 20 years. We assigned them to groups with self-, other-, dual- or no harm at specific assessments. Bullying victimization and relationship quality with classmates and teachers were assessed at 13 and 17. We estimated transition probabilities between the harm groups using latent Markov chain models. Results: At age 13, 3% of the sample engaged in dual-harm, 10% in self-harm only, and 7% in other-harm only. These percentages decreased in late adolescence. Initial dual-harm was often followed by sex-specific single-harm: most of the female participants transitioned to self-harm, and male participants to other-harm. Those in the initial dual-harm group were less likely to stop harming than those in the initial single-harm groups (p < 0.05). Adverse relationship experiences generally predicted harm. A positive teacher-student bond was associated with the cessation of single-harm. Conclusion: Single- and dual-harm in the form of physical injury typically emerge by mid-adolescence. After this point, adolescents commonly maintain harm, especially those who have presented with dual-harm. Helping adolescents cope with adverse relationship experiences and creating opportunities for positive relationship experiences could address these harmful behaviors

Self-, other-, and dual-harm during adolescence: a prospective-longitudinal study of childhood risk factors and early adult correlates

Background Little is known about the childhood antecedents and adult correlates of adolescent dual-harm (i.e. co-occurring self- and other-harm). We examine the longitudinal associations between (a) social and psychological risk factors in childhood and adolescent dual-harm and (b) adolescent dual-harm and social and mental health impairments in early adulthood. Methods Participants (N = 1482) are from a prospective longitudinal community-representative study. Dual-, self-, and other-harm were self-reported at ages 13, 15, and 17. Social and psychological risk factors in childhood were assessed between 7 and 11; early adult correlates at age 20. Groups with dual-harm, self-harm only, other-harm only, and no harm were compared. Results Between 13 and 17, 7.2% of adolescents reported dual-harm (self-harm only: 16.2%; other-harm only: 13.3%). Some childhood risk factors (e.g. sensation-seeking, parental divorce, victimization by peers) characterized all harm groups; others were common to the dual- and self-harm (anxiety/depressive symptoms, relational aggression) or dual- and other-harm groups only (low self-control, substance use, delinquency). Adolescents with dual-harm had reported more physical aggression and harsh parenting, and lower school bonding in childhood than any other group. In early adulthood, they reported more anxiety/depressive symptoms, psychopathy symptoms, homicidal ideations, delinquency, and victimization experiences than any other group. Conclusions Adolescent dual-harm follows psychological problems and social disconnection in childhood and signals risk of psychopathology and isolation in early adulthood. To curb the burden from dual-harm, interventions must target adolescents, families, peer networks, and school environments. Differentiating youth with dual-harm from those with single-harm is important for developing personalized treatments

Stressful Life Events in Different Social Contexts Are Associated With Self-Injury From Early Adolescence to Early Adulthood.

Self-injury often arises as a maladaptive coping strategy used to alleviate distress. Past research has typically examined how chronic stressors in a specific context are associated with self-injury. Little is known about the unique and cumulative associations between acute stressful life events that occur in different social contexts and self-injury among adolescents. This is especially the case for males, for whom the etiology of self-injury is understudied. We examine the unique and cumulative contributions of stressful life events in the contexts of adolescents' school life, peer networks, intimate relationships, and family life to self-injurious behavior in males and females from the community. Our data comes from a prospective-longitudinal community-representative study, the Zurich Project on the Social Development from Childhood to Adulthood (z-proso). Our sample consists of 1,482 adolescents (52% male) assessed at ages 13, 15, 17, and 20. At each age, adolescents reported whether they had engaged in self-injury during the previous month. They also reported stressful life events in the school, peer, intimate relationships, and family contexts, typically since the last assessment. Stressful life events in the peer context were consistently associated with self-injury. In the contexts of school, intimate relationships, and family, some associations were age- or sex-specific. For example, mid-adolescent females were more likely than mid-adolescent males to use self-injury when faced with stressful events in school and intimate relationships. With respect to risk accumulation, females' risk of self-injury increased with each additional life event between the ages of 13 and 17, beginning at 2+ events. This pattern did not hold for males. In early adulthood, 4+ life events were associated with an increased risk of self-injury, which suggests that the thresholds for the number of life events needed to trigger self-injury increased from adolescence to young adulthood. Our findings suggest that reducing risk of stressful events in different social contexts, and improving young people's coping skills could help reduce their risk of self-injury. New or revised theoretical models may be needed to better understand the emergence of self-injury in males

Is very high C-reactive protein in young adults associated with indicators of chronic disease risk?

Cases with very high C-reactive protein (CRP > 10 mg/l) are often dropped from analytic samples in research on risk for chronic physical and mental illness, but this convention could inadvertently result in excluding those most at risk. We tested whether young adults with very high CRP scored high on indicators of chronic disease risk. We also tested intergenerational pathways to and sex-differentiated correlates of very high CRP

Positive Prospective Mental Imagery Characteristics in Young Adults and Their Associations with Depressive Symptoms

Background Positive prospective mental imagery plays an important role in mental well-being, and depressive symptoms have been associated with difficulties in generating positive prospective mental images (PPMIs). We used a mobile app to gather PPMIs generated by young adults during the COVID-19 pandemic and analyzed content, characteristics, and associations with depressive symptoms. Methods This is a secondary analysis of a randomized controlled trial with 95 healthy young adults allocated into two groups (intervention and control). Participants used the mobile app decreasing mental health symptoms for seven consecutive days. Fifty participants in the intervention group reported PPMIs at least three times per day using a mobile app inducing PPMI generation. We categorized entries into themes and applied moderation models to investigate associations between PPMI characteristics and depressive symptoms. Results We distinguished 25 PPMI themes. The most frequent were related to consuming food and drinks, watching TV/streaming platforms, and doing sports. Vividness and ease of generation of PPMIs, but not their anticipation, pleasure intensity or number of engagements with the app were associated with fewer depressive symptoms. Conclusions We identified PPMI themes in young adults and found significant negative associations between depressive symptoms and vividness and generation ease of PPMIs. These results may inform prevention and intervention science, including the design of personalized interventions. We discuss implications for future studies and treatment development for individuals experiencing diminished PPMI

Parental supervision positively impacts children’s economic prospects two decades later: A prospective longitudinal study

Importance Upward income mobility is associated with better health outcomes and reduced stress. However, opportunities are unequally distributed, particularly so for those in rural communities and whose family have lower educational attainment. Objective To test the impact of parental supervision on their children’s income two decades later adjusting for parental economic and educational status. Design This study is a longitudinal, representative cohort study. From 1993–2000, annual assessments of 1,420 children were completed until age 16, then followed up at age 35, 2018–2021, for further assessment. Models tested direct effects of parental supervision on child income, and indirect effects via child educational attainment. Setting This study is an ongoing longitudinal population-based study of families in 11 predominately rural counties of the Southeastern U.S. Participants About 8% of the residents and sample are African American and fewer than 1% are Hispanic. American Indians make up 4% of the population in study but were oversampled to make up 25% of the sample. 49% of the 1,420 participants are female. Main outcomes and measures 1258 children and parents were assessed for sex, race/ethnicity, household income, parent educational attainment, family structure, child behavioral problems, and parental supervision. The children were followed up at age 35 to assess their household income and educational attainment. Results Parental educational attainment, income, and family structure were strongly associated with their children’s household income at age 35 (e.g., r = .392, p < .05). Parental supervision of the child was associated with increased household income for the child at age 35, adjusting for SES of the family of origin. Children of parents who did not engage in adequate supervision earned approximately $14,000 less/year (i.e., ~13% of the sample’s median household income) than those who did. The association of parental supervision and child income at 35 was mediated by the child’s educational attainment. Conclusion and relevance This study suggests adequate parental supervision during early adolescence is associated with children’s economic prospects two decades later, in part by improving their educational prospects. This is particularly important in areas such as rural Southeast U.S

Polysubstance Use in Early Adulthood: Patterns and Developmental Precursors in an Urban Cohort

Polysubstance use (i.e., simultaneous or sequential use of different psychoactive substances) is associated with increases in the risk of severe health problems and social impairments. The present study leverages community-representative, long-term longitudinal data from an urban cohort to assess: (a) the prevalence and continuation of polysubstance use between adolescence and early adulthood; (b) different patterns of polysubstance use (i.e., combinations of substances) in early adulthood; and (c) childhood risk factors for polysubstance use in early adulthood. At age 20 (n = 1,180), respondents provided comprehensive self-reported information on past-year substance use, including use of legal and illicit substances (e.g., cannabinoids, stimulants, and hallucinogens), and nonmedical use of prescription drugs (e.g., opioids, tranquilizers). In adolescence (ages 13–17), limited versions of this questionnaire were administered. In childhood (ages 7–11), potential risk factors, including individual-level factors (e.g., sensation-seeking, low self-control, aggression, and internalizing symptoms) and social-environmental factors (e.g., social stressors, exposure to others’ substance use), were assessed. We fitted latent class models to identify classes of participants with different substance use profiles in early adulthood. The results show that polysubstance use increased between early adolescence and early adulthood. The continuation of polysubstance use was common (stability between all adjacent assessments: odds ratio &gt;7). At age 20, more than one-third of participants reported polysubstance use (involving illicit substances, nonmedical use of prescription drugs, and cannabidiol). Four latent classes with polysubstance use were identified: (1) broad spectrum of substances; (2) cannabis and club drugs; (3) cannabis and the nonmedical use of prescription drugs; and (4) different cannabinoids. Risk factors for any polysubstance use included childhood sensation-seeking and exposure to others’ substance use; some childhood risk factors were differentially associated with the four classes (e.g., low self-control in childhood was associated with an increased likelihood of being in the broad spectrum class). The classes also differed with regard to socio-demographic factors. This study revealed that polysubstance use is a widespread and multifaceted phenomenon that typically emerges during adolescence. To facilitate the design of tailored prevention mechanisms, the heterogeneity of polysubstance use and respective socio-demographic and developmental precursors need to be considered

Disentangling the effects of self-control and the use of tobacco and cannabis on violence perpetration from childhood to early adulthood.

Associations among self-control, substance use (e.g., tobacco and cannabis use), and violence perpetration have been documented during the adolescent years, but the direction of these associations is not well understood. Using five assessments (covering 9 years) from a prospective-longitudinal study, we examined self-control as a precursor and subsequent mechanism of associations between adolescent substance use and physical violence perpetration. Data came from a large, ethnically diverse sample (n = 1,056). Youth reported their self-control at ages 11, 13, 15, 17, and 20; and their tobacco and cannabis use, and physical violence perpetration at ages 13, 15, 17, and 20. Cross-lagged panel analyses examined associations between these constructs over time. More self-control in late childhood and early adolescence was associated with less future tobacco and cannabis use and physical violence perpetration. Tobacco use was partially associated with more physical violence over time; these associations were not mediated by self-control. Tobacco use in early adolescence was associated with future cannabis use; during late adolescence, tobacco and cannabis use were reciprocally associated over time. Cannabis use was not associated with future physical violence perpetration. Early adolescent self-control plays an important role in later substance use and violence perpetration, and tobacco use has unique links with both later cannabis use and violence perpetration. Supporting the capacities for self-control in late childhood and early adolescence and preventing the initiation and use of entry-level substances could play an important role in preventing both substance use and violence perpetration and their many costs to society