The Child Trauma Prevention and Treatment (CTPT) Data Archive will address critical barriers to using existing data to improve interventions for children impacted by traumatic experiences. Exposure to trauma is unfortunately common for children and adolescents. Each year, tens of millions around the world experience trauma; a significant proportion develop traumatic stress or related sequelae that impact child health and functioning. Recent meta-analyses have found evidence for effectiveness of some preventative and treatment interventions with traumatized children, but many questions crucial to improving these interventions (eg, moderators and mediators of effectiveness) cannot be addressed with aggregate data. Single studies have small Ns that limit statistical power and the ability to examine potential demographic disparities in treatment effectiveness. Integrative cross-study analyses using individual patient data are crucial, but hindered by enormous practical barriers (access to data, effort required for dataset integration / harmonization). The CTPT Data Archive will address these critical barriers by gathering data from intervention studies around the world with children exposed to traumas such as injury, violence, or maltreatment; applying coding and metadata to facilitate cross-study harmonization; and making data and related tools and resources accessible to researchers. Developed in conjunction with the Global Collaboration on Traumatic Stress, the project advances `FAIR data principles' – making research data more Findable, Accessible, Interoperable, and Re-usable. We leverage the solid framework provided by the Prospective studies of Acute Child Trauma and Recovery (PACT/R) archive of non-intervention studies. Our overarching objective is to build an expandable research resource for the field that will enhance the utility and value of child trauma studies - and ultimately improve child trauma interventions - by facilitating integrative cross-study analyses. The project has the following specific aims: Aim 1: Initiate CTPT Archive with data from ≥ 25 intervention studies, representing >~2000 participants; Aim 2: Apply coding and metadata for individual- and study-level data elements to facilitate harmonization Aim 3: Ensure data preservation / accessibility and promote data use We will create tools and resources (including relevant syntax and algorithms) for researchers contributing or using CTPT data and disseminate these via the childtraumadata.org website, and will deposit standardized / harmonized datasets with an established repository to ensure long-term preservation and accessibility. This project advances NICHD's goal of archiving and documenting existing datasets within its scientific mission, enabling secondary analyses by the scientific community. The CTPT archive will be an ongoing research resource, taking in data and enabling novel analyses of how and for whom child trauma interventions work, so that we can effective...