{
  "schema_version": "2.0.0",
  "id": "nohynek-2012-pandemrix-narcolepsy",
  "name": "Finland Pandemrix childhood narcolepsy cohort (Nohynek)",
  "aliases": [
    "Finnish AS03/H1N1 vaccine narcolepsy cohort"
  ],
  "outbreak_event": "2009 H1N1 pandemic vaccination campaign (Finland)",
  "pathogen_id": "pandemrix-as03-h1n1",
  "pathogen_class": "vaccine",
  "exposure_ascertainment": "registry_code",
  "design": "registry_linkage",
  "denominator_defined": "yes",
  "denominator_method": "All children living in Finland born 1 Jan 1991 - 31 Dec 2005, with vaccination status from the national vaccination registry and narcolepsy cases from national health registries.",
  "recruitment_source": "population_registry",
  "time_zero_definition": "Receipt (or non-receipt) of AS03-adjuvanted Pandemrix H1N1 vaccine during the 2009-10 campaign",
  "time_zero_precision": "month",
  "control_group": "unexposed_unmatched",
  "control_matching_variables": [],
  "n_source_population": null,
  "n_enrolled": null,
  "n_analysed": 67,
  "followups": [],
  "max_followup_months": null,
  "instruments": [],
  "case_definition": "not_applicable",
  "pem_assessed": "no",
  "objective_measures": [
    "polysomnography"
  ],
  "specimens_collected": false,
  "specimen_types": [],
  "acute_phase_specimens": "not_applicable",
  "storage": null,
  "biobank_status": "not_applicable",
  "consent_future_use": "not_applicable",
  "external_access": "not_applicable",
  "contact": null,
  "registration_id": null,
  "funders": [
    "National Institute for Health and Welfare (THL), Finland"
  ],
  "conflicts": null,
  "data_availability": null,
  "notes": "Population registry-linkage cohort covering all Finnish children in the birth range, comparing narcolepsy incidence between Pandemrix-vaccinated and unvaccinated children (vaccine coverage 75%). Included to span the vaccine trigger class: the strongest example of an immune-mediated (autoimmune) post-exposure sequela with a defined denominator and an unvaccinated comparator. Of 67 confirmed cases, 46 vaccinated and 7 unvaccinated entered the primary analysis.",
  "publications": [
    {
      "id": "nohynek-2012",
      "title": "AS03 adjuvanted AH1N1 vaccine associated with an abrupt increase in the incidence of childhood narcolepsy in Finland",
      "authors": "Nohynek H, Jokinen J, Partinen M, et al.",
      "year": 2012,
      "journal": "PLoS ONE",
      "doi": "10.1371/journal.pone.0033536",
      "pmid": "22470453",
      "url": "https://pubmed.ncbi.nlm.nih.gov/22470453/",
      "open_access": true,
      "is_primary_cohort_paper": true
    }
  ],
  "symptom_inventory_scope": "none",
  "n_symptoms_queried": null,
  "symptom_instrument_note": null,
  "related_cohorts": [],
  "last_verified": "2026-07-20",
  "verified_by": "OSMF research-tracker (web-verified against source)",
  "harmonisation_ruleset": "pais-harmony-v1",
  "observations": [
    {
      "id": "narcolepsy-rate-ratio",
      "cohort_id": "nohynek-2012-pandemrix-narcolepsy",
      "publication_id": "nohynek-2012",
      "schema_version": "2.0.0",
      "measure_id": "event:narcolepsy",
      "measure_verbatim": "narcolepsy incidence 9.0 per 100 000 person-years in vaccinated vs 0.7 in unvaccinated children (rate ratio 12.7)",
      "population": {
        "scope": "whole_cohort",
        "stratum": null,
        "denominator_basis": "person_time",
        "n_assessed": {
          "status": "measured_not_reported"
        }
      },
      "timing": {
        "timepoint_months": null,
        "timepoint_band": "unspecified",
        "reference_period": "not_reported",
        "is_cumulative": false
      },
      "method": {
        "ascertainment": "unclear",
        "instrument_id": null,
        "severity_threshold": null,
        "blinded_assessment": "not_reported"
      },
      "value": {
        "type": "rate",
        "events": 46,
        "person_time": {
          "status": "measured_not_reported"
        },
        "person_time_unit": "per 100000 person-years",
        "rate": 9.0,
        "ci": null
      },
      "comparator": {
        "group": "unexposed_unmatched",
        "value": {
          "type": "rate",
          "rate": 0.7,
          "person_time_unit": "per 100000 person-years"
        },
        "effect": {
          "estimate": 12.7,
          "effect_type": "rr",
          "ci": [
            6.1,
            30.8
          ]
        }
      },
      "harmonised": null,
      "provenance": {
        "source_locator": "Results/Abstract (rate ratio 12.7, 95% CI 6.1-30.8)",
        "extracted_by": null,
        "extracted_on": null,
        "verified_by": "OSMF research-tracker (web-verified against source)",
        "verified_on": "2026-07-20",
        "extraction_method": "manual"
      }
    }
  ]
}