{
  "abstract": "Introduction: Adverse childhood experiences (ACEs) are associated with poor health outcomes, with higher cumulative exposure conveying more risk. Although earlier ACE studies focus on household-level adversities, growing evidence explores traumatic childhood experiences originating outside the home (expanded ACEs). Expanded ACEs may co-occur with household-level ACEs, causing misclassification bias if not measured. A comprehensive list of expanded ACEs has not been identified, and no unified framework exists to consider their impacts. This systematic review will identify expanded ACEs published in peer-reviewed literature and examine their associations with physical and mental health outcomes and behaviours by demographic subgroups, offering the first unified framework for expanded ACEs’ impacts on health.\n\nMethods and analysis: Six databases were systematically searched in February 2026 for global, peer-reviewed studies published in English since database inception: PubMed/Medline, Embase, CINAHL, PsycInfo, CENTRAL and Scopus. Eligibility includes studies involving humans without restriction to date, setting, population or location; studies with ACEs originating outside the home as the exposure; and studies with outcomes including physical or mental health outcomes anchored to International Classification of Diseases, 10th revision or Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition codes or behaviours.\n\nResearchers (RAs) screen titles/abstracts using pre-established eligibility criteria on training batches of 30–50 articles with faculty oversight. Once agreement consistently reaches 80%, RAs may use a hybrid screening process that prioritises independent, dual screening, relying on single-screening with fidelity checks to stay within budget and timeline, while maintaining rigour. Title/abstract screening is followed by full-text review and extraction. Study quality will be assessed using validated tools, with limitations reported. Data will be summarised via quantitative synthesis or narrative summary as appropriate.\n\nEthics and dissemination: The University of Pennsylvania #26-7542 determined this work is not human subjects research. Dissemination will occur through peer-reviewed presentations and publications.\n\nPROSPERO registration number: CRD420261432925.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Family Medicine and Community Health, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA",
    "Center for Public Health, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA",
    "Leonard Davis Institute of Health Economics (LDI), University of Pennsylvania, Philadelphia, Pennsylvania, USA",
    "Center for Violence Prevention, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA",
    "Division of General Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA",
    "Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA",
    "Holman Biotech Commons, University of Pennsylvania Libraries, Philadelphia, Pennsylvania, USA",
    "Department of Social and Behavioral Sciences, College of Public Health, Temple University, Philadelphia, Pennsylvania, USA",
    "Department of Psychiatry & Behavioral Science, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania, USA",
    "Department of Clinical, Educational & Health Psychology, Division of Psychology & Language Sciences, University College London, London, UK"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0,
        1,
        2,
        3
      ],
      "name": "Christine M Forke",
      "orcid": "0000-0002-2262-8363"
    },
    {
      "affs": [
        4,
        5
      ],
      "name": "Roy Wade"
    },
    {
      "affs": [
        6
      ],
      "name": "Jennifer Lege"
    },
    {
      "affs": [
        7,
        8,
        9
      ],
      "name": "Yaara Zisman-Ilani",
      "orcid": "0000-0001-6852-2583"
    },
    {
      "affs": [
        0,
        2
      ],
      "name": "Peter F Cronholm"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fqbr7gpg1nvbr.bib",
  "cited_by": 0,
  "doi": "10.1136/bmjopen-2026-125469",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13723859/",
  "id": "fqbr7gpg1nvbr",
  "issns": [
    "2044-6055",
    "2044-6055"
  ],
  "landing_url": "https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2026-125469",
  "language": "en",
  "licence": "CC-BY-NC-4.0",
  "licence_label": "CC BY-NC 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
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    ],
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    [
      "heading",
      "Protocol"
    ],
    [
      "heading",
      "Public Health"
    ],
    [
      "openalex",
      "3203|Child Abuse and Trauma"
    ]
  ],
  "openalex": "W7224097650",
  "pdf_url": null,
  "pmcid": "PMC13723859",
  "pmid": "42951300",
  "published": "2026-10-28",
  "publisher": "BMJ",
  "ris": "https://research.draconitic.com/paper/fqbr7gpg1nvbr.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:44Z",
      "native_id": "10.1136/bmjopen-2026-125469",
      "source": "crossref",
      "url": "https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2026-125469"
    },
    {
      "first_seen": "2026-11-04T12:22:25Z",
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  "subjects": [
    {
      "field": "medicine",
      "origin": "heading:Public Health",
      "subfield": "epidemiology-public-health"
    }
  ],
  "title": "Identifying expanded adverse childhood experiences and examining their relationship with health outcomes: a systematic review protocol",
  "title_text": "Identifying expanded adverse childhood experiences and examining their relationship with health outcomes: a systematic review protocol",
  "type": "peer-reviewed",
  "updated_at": "2026-11-05T12:20:36Z",
  "url": "https://research.draconitic.com/paper/fqbr7gpg1nvbr",
  "venue": "BMJ Open",
  "versions": []
}