Polyvictimization and developmental trauma in childhood

Background: Polyvictimization (Gilbar & Ford, 2020) and developmental trauma (van der Kolk, Ford, & Spinazzola, 2019) have been identified in the past decade as empirically operationalized high impact forms of cumulative childhood trauma (Ford, 2015). Childhood polyvictimization (PV) is defined as experiencing multiple types of interpersonal victimization sequentially or concurrently at any point in childhood (lifetime) or in the past year (recent). Childhood developmental trauma (DT) is defined as a combination of traumatic interpersonal victimization and disruption in attachment bonds with primary caregiver(s). Objective: To present an overview of research findings to date and a systematic agenda for research on polyvictimization and developmental trauma over the next decade. Method: A systematic review of research on polyvictimization and developmental trauma in childhood was conducted in peer-reviewed publications from 2010 to 2020. Results: More than 100 empirical studies of PV or DT were reviewed. Childhood PV was associated with both the risk and severity of internalizing and externalizing disorders, specifically with PTSD when victimization is sufficiently severe to be traumatic. Childhood DT was associated with dysregulation in three domains (affective/physiological, attentional/behavioural, self/relational) that can be reliably and validly assessed with 15 symptoms that are distinct from the symptoms of ICD-11 PTSD and complex PTSD (see Table 1). Research is needed to prospectively determine, within and across the developmental epochs of childhood and adolescence: (1) how the specific types of traumatic victimization in PV and DT differ or remain constant; (2) if and how PV and DT co-occur or diverge both on a linear and a quadratic basis; (3) the form and timing/sequencing of the separate and shared biopsychosocial sequelae of PV and DT; (4) the association of PV and DT with diagnoses of internalizing (including PTSD/cPTSD) and externalizing disorders, and severe comorbidities (e.g., self-harm, school failure, juvenile delinquency, medical illness); (5) protective factors and resilience and recovery trajectories; (6) short- and long-term response to evidence-based psychotherapies and mediators/mechanisms of symptom and impairment reduction. Conclusions: Polyvictimization and developmental trauma operationalize the broad construct of complex trauma, and parallel but are, respectively, more comprehensive and more attachment/relationally focused than the adverse childhood experiences construct.