Analyzing transdiagnostic internalizing symptoms in a global sample of trauma-exposed children using pooled individual participant data: a latent transition analysis

Background: Children often experience both posttraumatic stress (PTS) and depression after potentially traumatic events (PTEs). Latent class analyses (LCAs) identify subgroups with different co-occurring symptoms, but little is known about what predicts transitions between these symptom classes over time. Analyzing these transitions could reveal factors that influence the shift to classes with fewer internalizing symptoms. Methods: Using harmonized individual participant data (n = 787) from nine studies (United States, United Kingdom, Australia, and Switzerland) included in the Prospective studies of Acute Child Trauma and Recovery Data Archive (PACT/R), internalizing symptom classes (using PTS and depression items) were identified using LCAs for T1 (0–2 months posttrauma) and T2 (3–15 months posttrauma) separately. Latent transition analysis was used to examine predictors of transitions across symptom classes over time. Included predictors were age, gender, minority status, and trauma type. Results: Five classes were identified at both time points: ‘low internalizing’ class (T1: 20%; T2: 40%), ‘low PTS/moderate-high depression’ class (T1: 20%; T2: 27%), ‘moderate internalizing’ class (T1: 25%; T2: 12%), ‘moderate PTS/high depression’ class (T1: 17%, T2: 14%), and ‘high internalizing’ class (T1: 16%, T2: 6%). ‘Low internalizing’ was the most common and stable response (87% stayed in this class). At both time points, 40% of all children were classified into either a ‘low PTS/moderate-high depression’ class or a ‘moderate PTS/high depression’ class. Children belonging to minority groups in their country of residence and children exposed to interpersonal PTEs were less likely to transition from the ‘high internalizing’ class to lower symptom classes. Conclusions: Most children show low PTS and depression symptoms after PTEs. When symptoms do develop, they usually involve both high depression and PTS, rather than high PTS with low depression. This underscores the importance of assessing both conditions and developing interventions that target multiple disorders. Minority children exposed to interpersonal trauma require special focus in research and treatment.