Understanding Co-Occurrence of Mental Health Problems in Youth within the Research Domain Criteria (RDoC) Framework: A Scoping Review Study

Background and Purpose: High rates of co-occurring mental health problems, or comorbidity, have triggered a growing body of person-centered literature to understand the grouping structure of youth comorbidity by identifying meaningful patterns of associated symptoms and validating patterns with antecedents. The National Institute of Mental Health’s Research Domain Criteria (RDoC) offers an etiological framework for identifying cognitive, affective, and social constructs organized around major functioning domains, which can be assessed in multiple units, including physiology, behavior, and self-report. This scoping review 1) mapped the scope of person-centered comorbidity studies to determine youth comorbidity patterns; 2) summarized and critically analyzed the RDoC-informed antecedents of comorbidity patterns.

Methods: Eligible studies through June 2023 were searched using PubMed, CINAHL, APA PsycArticles, APA PsycInfo, and Web of Science. Included peer-reviewed articles had to examine comorbidity patterns and measure youth mental health between birth and 17 years of age. Three researchers independently assessed each article, and team discussion resolved conflicting decisions. After deduplication of the searches, 1,318 articles were screened; 100 were assessed for eligibility. Of the full-text articles, 30 were eligible for our review.

Results: Included studies were published between 1996 and 2022, with 47% in the past five years, 47% conducted in the United States, 73% with sample sizes greater than 500, and 37% longitudinal. In all studies, one general psychopathology pattern, with a higher probability of all assessed mental health symptoms, was identified. One normative, resilient pattern was identified across studies. In addition, specific patterns, such as internalizing and externalizing patterns, that reflected unique covariances among the assessed symptoms were identified. The number of specific patterns ranged from one to six across studies.

Thirty-eight antecedents from eleven studies (37%) were classified as RDoC constructs of Negative Valence Systems (n = 8; e.g., irritability), Positive Valence Systems (n = 1; i.e., rigidity–flexibility), Cognitive Systems (n = 9; e.g., visuospatial processing), Systems for Social Processes (n = 14; e.g., social disinhibition), Arousal and Regulatory Systems (n = 5; e.g., rhythmicity-sleep), and Sensorimotor systems (n = 1; i.e., sensorimotor functioning). Of these, 22 RDoC-informed antecedents (58%) were differentially related to the identified patterns. All RDoC constructs were the self-report unit of analysis, except 4 behavioral constructs.

Conclusions and Implications: The identified comorbidity patterns support an emerging conceptualization of comorbidity structure assuming psychopathology as hierarchical and composed of broader factors, involving one general and other specific psychopathology factors, representing underlying processes indicating individuals’ propensities to develop all kinds or specific forms of psychopathologies. Variation in the number and/or composition of specific patterns may reflect variability in the breadth of assessed symptoms or respective measures. Future studies should cross-validate the youth comorbidity structure using complementary variable-centered approaches.

More rigorous incorporation of novel RDoC-informed antecedents, assessed at physiological and behavioral units of analysis, into youth mental health studies will advance our knowledge, which has practical implications for informing evidence-based preventive protocols to effectively detect susceptibility underlying psychopathology. Further investigation of the interactions between RDoC domains and the environment and consideration of developmental factors will elucidate our knowledge.