Observational neuroimaging studies with children and adolescents may identify neurological anomalies and other clinically relevant findings. Planning for the management of this information involves ethical considerations that may influence informed consent, confidentiality, and communication with participants about assessment results. Biomedical ethics principles include respect for autonomy, beneficence, non-maleficence, and justice. Each project presents unique challenges. The Adolescent Brain and Cognitive Development study (ABCD) collaborators have systematically developed recommendations with written guidelines for identifying and responding to potential risks that adhere to biomedical ethics principles. To illustrate, we will review the ABCD approach to three areas: (1) hazardous substance use; (2) neurological anomalies; and (3) imminent potential for self-harm or harm to others. Each ABCD site is responsible for implementing procedures consistent with these guidelines in accordance with their Institutional Review Board approved protocols, state regulations, and local resources. To assure that each site has related plans and resources in place, site emergency procedures manuals have been developed, documented and reviewed for adherence to ABCD guidelines. This article will describe the principles and process used to develop these ABCD bioethics and medical oversight guidelines, the concerns and options considered, and the resulting approaches advised to sites.

This is a report of developmental trajectories of cortical surface area and cortical volume in the NIH MRI Study of Normal Brain Development. The quality-controlled sample included 384 individual typically-developing subjects with repeated scanning (1-3 per subject, total scans n=753) from 4.9 to 22.3 years of age. The best-fit model (cubic, quadratic, or first-order linear) was identified at each vertex using mixed-effects models, with statistical correction for multiple comparisons using random field theory. Analyses were performed with and without controlling for total brain volume. These data are provided for reference and comparison with other databases. Further discussion and interpretation on cortical developmental trajectories can be found in the associated Ducharme et al.׳s article "Trajectories of cortical thickness maturation in normal brain development - the importance of quality control procedures" (Ducharme et al., 2015) [1].

The Adolescent Brain and Cognitive Development (ABCD) Study incorporates a comprehensive range of measures assessing predictors and outcomes related to both mental and physical health across childhood and adolescence. The workgroup developed a battery that would assess a comprehensive range of domains that address study aims while minimizing participant and family burden. We review the major considerations that went into deciding what constructs to cover in the demographics, physical health and mental health domains, as well as the process of selecting measures, piloting and refining the originally proposed battery. We present a description of the baseline battery, as well as the six-month interim assessments and the one-year follow-up assessments. This battery includes assessments from the perspectives of both the parent and the target youth, as well as teacher reports. This battery will provide a foundational baseline assessment of the youth's current function so as to permit characterization of stability and change in key domains over time. The findings from this battery will also be utilized to identify both resilience markers that predict healthy development and risk factors for later adverse outcomes in physical health, mental health, and substance use and abuse.

The Adolescent Brain Cognitive Development (ABCD) Study of 11,880 youth incorporates a comprehensive range of measures assessing predictors and outcomes related to mental health across childhood and adolescence in participating youth, as well as information about family mental health history. We have previously described the logic and content of the mental health assessment battery at Baseline and 1-year follow-up. Here, we describe changes to that battery and issues and clarifications that have emerged, as well as additions to the mental health battery at the 2-, 3-, 4-, and 5-year follow-ups. We capitalize on the recent release of longitudinal data for caregiver and youth report of mental health data to evaluate trajectories of dimensions of psychopathology as a function of demographic factors. For both caregiver and self-reported mental health symptoms, males showed age-related decreases in internalizing and externalizing symptoms, while females showed an increase in internalizing symptoms with age. Multiple indicators of socioeconomic status (caregiver education, family income, financial adversity, neighborhood poverty) accounted for unique variance in both caregiver and youth-reported externalizing and internalizing symptoms. These data highlight the importance of examining developmental trajectories of mental health as a function of key factors such as sex and socioeconomic environment.