{
  "abstract": "Background: Ecological momentary assessment (EMA) captures experience and behavior as they occur in daily life, yielding intensive longitudinal data that are well suited for modeling within- and between-person processes and outcomes. However, heterogeneity in EMA items across studies hampers comparability, data aggregation, and reproducibility. Objective: To establish expert consensus on an EMA core item set, a standardized set of momentary variables from which comparable phenotypic indicators can later be derived. This minimum item set aims to be broadly applicable yet concise enough for use in large-scale research consortia and routine care while maintaining minimal completion time and assessment burden, adopting a nested structure (i.e., minimum core, extended core, add-on modules). Methods: A Delphi study was conducted with support from an international expert panel (J.S., P.K., I.M-G., P.W., M.L.) and 50 invited EMA experts from the German Center for Mental Health (DZPG). Candidate items were derived from prior work, the international expert panel, as well as a narrative review. The items were iteratively refined between Delphi rounds based on aggregated ratings and expert comments. They were assigned to one of three layers – the minimum core, extended core, or add-on modules – according to their degree of generality, the minimum core comprising the most broadly applicable items. A priori consensus was set at ≥75% endorsement. Rating stability and qualitative agreement informed revisions. Experts additionally reported on current methodological EMA practices (e.g., sampling frequency, study duration). Results: The EMA core phenotype was established in three rounds. Participation was n=41 in Round 1 (82%), n=43 in Round 2 (86%), and n=40 in Round 3 (80%). Of 69 initial item candidates, 37 partly revised items remained in the three-tiered structure. The finalized EMA minimum core (7 items) comprises four affect items, one item on social context, and two items on positive and negative events. The EMA extended core includes 5 additional items (total 12) on affect, social context, and activities. Completion time for both the minimum and extended core remains low. More specific items (e.g., self-esteem) are reserved for more specific EMA add-on modules. Conclusions: The consensus-derived DZPG EMA core phenotype provides a consented, ready-to-use item set that balances information yield with minimal assessment burden. By harmonizing EMA assessment across studies, it facilitates comparability, data pooling, and reproducible research while supporting integration into large-scale digital mental health assessment and intervention pipelines. The EMA core will be maintained as a living, versioned measure. Ongoing initiatives include a prospectively specified, multi-study validation program of items, systematic variation of design and assessment procedures (e.g., answering formats), as well as cross-cultural adaptation of the EMA core phenotype.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "name": "Christian Rauschenberg"
    },
    {
      "name": "Annette Brose"
    },
    {
      "name": "Joshua M. Smyth"
    },
    {
      "name": "Peter Kuppens"
    },
    {
      "name": "Peter Wilhelm"
    },
    {
      "name": "Inez Myin-Germeys"
    },
    {
      "name": "Harald Baumeister"
    },
    {
      "name": "Christine Knaevelsrud"
    },
    {
      "name": "Pascal-M. Aggensteiner"
    },
    {
      "name": "Patrick Bach"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/83hy60hd52t2q.bib",
  "cited_by": 0,
  "doi": "10.31234/osf.io/g7ykv_v2",
  "fulltext_url": null,
  "id": "83hy60hd52t2q",
  "issns": [],
  "landing_url": "https://osf.io/preprints/psyarxiv/g7ykv_v2/",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "bepress",
      "Clinical Psychology"
    ],
    [
      "bepress",
      "Emotion"
    ],
    [
      "bepress",
      "Health Psychology"
    ],
    [
      "bepress",
      "Life Sciences"
    ],
    [
      "bepress",
      "Neuroscience"
    ],
    [
      "bepress",
      "Psychiatry"
    ],
    [
      "bepress",
      "Social and Behavioral Sciences"
    ],
    [
      "openalex",
      "3205|Mental Health Research Topics"
    ]
  ],
  "openalex": "W7213504361",
  "pdf_url": "https://osf.io/g7ykv/download",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-17",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/83hy60hd52t2q.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:33Z",
      "native_id": "g7ykv",
      "source": "osf",
      "url": "https://osf.io/preprints/psyarxiv/g7ykv_v2/"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "bepress:Neuroscience",
      "subfield": "neuroscience"
    },
    {
      "field": "medicine",
      "origin": "bepress:Clinical Psychology",
      "subfield": "psychiatry"
    }
  ],
  "title": "Toward Harmonizing Ecological Momentary Assessment (EMA) in Mental Health Research and Services: A Delphi Study on an EMA Core Item Set",
  "title_text": "Toward Harmonizing Ecological Momentary Assessment (EMA) in Mental Health Research and Services: A Delphi Study on an EMA Core Item Set",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:33Z",
  "url": "https://research.draconitic.com/paper/83hy60hd52t2q",
  "venue": "PsyArXiv",
  "versions": []
}