{
  "release_id": "f6f6f1b6f50379ed",
  "id": "cardio:apple-heart-study",
  "owner": "cardio",
  "kind": "study",
  "slug": "apple-heart-study",
  "name": "Apple Heart Study",
  "aliases": [
    "AHS"
  ],
  "atlases": [
    "cardio"
  ],
  "summary_plain": "A large US study of whether a smartwatch alert for an irregular pulse matches atrial fibrillation on an ECG. People with a compatible iPhone and Apple Watch who reported no atrial fibrillation joined through an app. Those who got an alert were offered a telemedicine visit and a mailed ECG patch. The study checked how often alerts matched the ECG. It did not test whether alerts prevent strokes.",
  "summary_technical": "Single-group, siteless, pragmatic study (NCT03335800), sponsored by Apple Inc. with Stanford University as registry collaborator; the registry names two principal investigators, both at Stanford. The registry records an interventional study, phase not applicable, allocation not applicable, one arm, no masking and primary purpose screening. Enrollment differs by source: the registry gives 419927 (actual) and the abstract of the main paper says 419,297 participants were recruited. The sources do not explain the difference and it is not reconciled. The registry lists two primary outcomes (AF on ambulatory ECG among notified participants, and confirmed AF with a detection by an app component) and two secondary outcomes (concordance with the app algorithm notification, and self-reported contact with a health care provider). No findings are recorded as structured rows here; the results are in the claim for the technology.",
  "editorial_state": "draft",
  "last_substantive_edit": "2026-10-15",
  "last_evidence_check": "2026-10-14",
  "next_review_due": null,
  "identifiers": [
    {
      "scheme": "nct",
      "value": "NCT03335800",
      "normalized_value": "NCT03335800",
      "match": "exact",
      "version": null,
      "label": null,
      "from_source": false
    }
  ],
  "navigation": {
    "cardio": {
      "condition-area": [
        "arrhythmias"
      ]
    }
  },
  "payload": {
    "design": "Single-group, siteless, pragmatic study. The registry gives allocation not applicable, one arm, no masking and primary purpose screening. A smartwatch irregular-pulse notification algorithm flagged possible atrial fibrillation, which started a telemedicine visit and a mailed ECG patch to wear for up to 7 days (abstract).",
    "drug_phase": "not_applicable",
    "registry_statuses": [
      {
        "status": "COMPLETED",
        "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
      }
    ],
    "start_date": {
      "date": "2017-11-29",
      "type": "actual",
      "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
    },
    "primary_completion_date": {
      "date": "2019-02-21",
      "type": "actual",
      "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
    },
    "completion_date": {
      "date": "2019-02-21",
      "type": "actual",
      "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
    },
    "results_first_posted": {
      "date": "2020-03-30",
      "type": null,
      "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
    },
    "countries": [
      {
        "code": "US",
        "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
      }
    ],
    "care_setting": {
      "description": "Remote and siteless. Participants consented through a smartphone app and no on-site visits were required. After an alert, follow-up used a telemedicine visit and a mailed ECG patch.",
      "snapshot": "cardio:pubmed-31722151-2026-10-14"
    },
    "stopped_early": null,
    "enrollment": [
      {
        "count": 419927,
        "basis": "enrolled",
        "unit": "participants",
        "snapshot": "cardio:ctgov-nct03335800-2026-10-14"
      },
      {
        "count": 419297,
        "basis": "enrolled",
        "unit": "participants",
        "snapshot": "cardio:pubmed-31722151-2026-10-14"
      }
    ],
    "arms": [
      {
        "id": "cardio:apple-heart-study-arm-app",
        "label": "Apple Heart Study App",
        "intervention": null,
        "description": "Participants without self-reported atrial fibrillation used a smartphone app to consent to monitoring. If a smartwatch-based irregular pulse notification algorithm identified possible atrial fibrillation, a telemedicine visit was started and an ECG patch was mailed to wear for up to 7 days."
      }
    ],
    "findings": []
  },
  "content_digest": "dbbab2122db325106ec439de370a090ed2c266b98e7e68f9125485ff25d59d62",
  "review": {
    "content_digest": "dbbab2122db325106ec439de370a090ed2c266b98e7e68f9125485ff25d59d62",
    "current": [],
    "conflicting": [],
    "stale": [],
    "inactive": []
  },
  "claims": [],
  "decisions": [],
  "milestones": [],
  "relationships": {
    "outgoing": [
      {
        "predicate": "investigates",
        "label": "Tests wristwatch-based photoplethysmography to identify arrhythmias",
        "clinical_claim_not_fact": false,
        "family": "sourced",
        "other_entity_id": "cardio:wearable-rhythm-detection",
        "other_entity_in_atlas": true,
        "claim_id": null,
        "evidence": {
          "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
          "locator": "protocolSection.identificationModule.officialTitle"
        },
        "primary": false,
        "role": null,
        "valid_from": null,
        "valid_to": null
      },
      {
        "predicate": "investigates",
        "label": "Lists atrial fibrillation as its first condition",
        "clinical_claim_not_fact": false,
        "family": "sourced",
        "other_entity_id": "cardio:atrial-fibrillation",
        "other_entity_in_atlas": true,
        "claim_id": null,
        "evidence": {
          "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
          "locator": "protocolSection.conditionsModule.conditions[0]"
        },
        "primary": false,
        "role": null,
        "valid_from": null,
        "valid_to": null
      },
      {
        "predicate": "sponsored_by",
        "label": "Lead sponsor",
        "clinical_claim_not_fact": false,
        "family": "sourced",
        "other_entity_id": "cardio:apple",
        "other_entity_in_atlas": true,
        "claim_id": null,
        "evidence": {
          "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
          "locator": "protocolSection.sponsorCollaboratorsModule.leadSponsor.name"
        },
        "primary": false,
        "role": "lead",
        "valid_from": null,
        "valid_to": null
      },
      {
        "predicate": "results_reported_in",
        "label": "Main results, NEJM 2019",
        "clinical_claim_not_fact": false,
        "family": "sourced",
        "other_entity_id": "cardio:pub-apple-heart-study-nejm-2019",
        "other_entity_in_atlas": true,
        "claim_id": null,
        "evidence": {
          "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
          "locator": "Abstract, CONCLUSIONS, final sentence (names NCT03335800)"
        },
        "primary": false,
        "role": null,
        "valid_from": null,
        "valid_to": null
      }
    ],
    "incoming": []
  },
  "page_path": "studies/apple-heart-study/",
  "context_path": "api/v1/context/cardio--apple-heart-study.md"
}