{
  "schema_version": "2.0.0",
  "id": "recover-adult-long-covid",
  "name": "NIH RECOVER-Adult Cohort",
  "aliases": [
    "RECOVER",
    "RECOVER-Adult",
    "Researching COVID to Enhance Recovery"
  ],
  "outbreak_event": "COVID-19 pandemic (2020–)",
  "pathogen_id": "sars-cov-2",
  "pathogen_class": "virus",
  "exposure_ascertainment": "pcr",
  "design": "prospective_non_inception",
  "denominator_defined": "yes",
  "denominator_method": "Nationwide multi-site US cohort enrolling SARS-CoV-2 positive and negative adults from >200 sites. Enrolment began in 2021, enrolling both acute and post-acute participants with retrospective infection ascertainment and prospective follow-up.",
  "recruitment_source": "mixed",
  "time_zero_definition": "Date of first positive SARS-CoV-2 PCR or antigen test",
  "time_zero_precision": "month",
  "control_group": "unexposed_unmatched",
  "control_matching_variables": ["general_population"],
  "n_source_population": null,
  "n_enrolled": 15000,
  "n_analysed": null,
  "followups": [
    {
      "months": 3,
      "n_assessed": null,
      "n_lost": null
    },
    {
      "months": 6,
      "n_assessed": null,
      "n_lost": null
    },
    {
      "months": 12,
      "n_assessed": null,
      "n_lost": null
    },
    {
      "months": 24,
      "n_assessed": null,
      "n_lost": null
    },
    {
      "months": 48,
      "n_assessed": null,
      "n_lost": null
    }
  ],
  "max_followup_months": 48,
  "instruments": [
    "sf-36",
    "promis-fatigue"
  ],
  "case_definition": "who_pcc_2021",
  "pem_assessed": "yes_single_item",
  "objective_measures": [
    "lab_panel",
    "imaging",
    "other_biopsy"
  ],
  "specimens_collected": true,
  "specimen_types": [
    "serum",
    "plasma",
    "pbmc",
    "whole_blood",
    "urine",
    "saliva"
  ],
  "acute_phase_specimens": "yes",
  "storage": "Centralised RECOVER biorepository at multiple academic medical centres",
  "biobank_status": "active",
  "consent_future_use": "broad",
  "external_access": "open_application",
  "contact": "NIH RECOVER Consortium",
  "registration_id": "NCT05172024",
  "funders": [
    "National Institutes of Health (NIH), USA"
  ],
  "conflicts": null,
  "data_availability": "De-identified data available via NIH data-sharing platform; biospecimens via application to RECOVER biorepository",
  "notes": "The flagship US Long COVID study: the largest prospective, controlled Long COVID cohort globally. Enrols SARS-CoV-2 positive adults across the full spectrum (asymptomatic through severe acute COVID) plus SARS-CoV-2 negative controls from the same communities. Standardised protocol across >200 sites with harmonised data collection, imaging, and biospecimen banking. Acute-phase and convalescent specimens banked — this is the most important specimen-banking Long COVID cohort. Multiple substudies are publishing as the cohort matures; add publications and observations iteratively as substudies report. The design is prospective but non-inception (many participants enrolled post-acutely with retrospective infection date); this is recorded in the design field. The denominator is defined (all enrolled with confirmed SARS-CoV-2 status) but the source population denominator is the catchment areas of the 200+ sites, not a closed population.",
  "publications": [
    {
      "id": "recover-horwitz-2023-design",
      "title": "Researching COVID to Enhance Recovery (RECOVER) adult study protocol: Rationale, objectives, and design",
      "authors": "Horwitz LI, Thaweethai T, Brosnahan KB, et al.",
      "year": 2023,
      "journal": "PLoS ONE",
      "doi": "10.1371/journal.pone.0274991",
      "pmid": "36075778",
      "url": "https://pubmed.ncbi.nlm.nih.gov/36075778/",
      "open_access": true,
      "is_primary_cohort_paper": true
    }
  ],
  "symptom_inventory_scope": "comprehensive_inventory",
  "n_symptoms_queried": null,
  "symptom_instrument_note": "Standardised symptom inventory across all sites; instruments include PROMIS scales, SF-36, and a RECOVER-specific symptom questionnaire covering ~35 symptoms across multiple domains. Full instruments listed in protocol.",
  "related_cohorts": [],
  "last_verified": "2026-07-21",
  "verified_by": "OSMF research-tracker (web-verified against source)",
  "harmonisation_ruleset": "pais-harmony-v1",
  "flags": [],
  "observations": [
    {
      "id": "recover-design-n-enrolled",
      "cohort_id": "recover-adult-long-covid",
      "publication_id": "recover-horwitz-2023-design",
      "schema_version": "2.0.0",
      "measure_id": "sym:fatigue",
      "measure_verbatim": "Cohort N enrolled: ~15,000 adults (SARS-CoV-2 positive and negative)",
      "population": {
        "scope": "whole_cohort",
        "stratum": null,
        "denominator_basis": "assessed_at_timepoint",
        "n_assessed": 15000
      },
      "timing": {
        "timepoint_months": 0,
        "timepoint_band": "acute",
        "reference_period": "not_applicable",
        "is_cumulative": false
      },
      "method": {
        "ascertainment": "registry_linkage",
        "instrument_id": null,
        "severity_threshold": null,
        "blinded_assessment": "not_applicable"
      },
      "value": {
        "type": "count",
        "n": 15000,
        "denominator": { "status": "not_applicable" },
        "precision": "approximate"
      },
      "comparator": {
        "group": "none",
        "value": { "status": "not_applicable" },
        "effect": null
      },
      "harmonised": null,
      "provenance": {
        "source_locator": "Horwitz 2023, Abstract & Methods (~15,000 adults to be enrolled across >200 US sites)",
        "extracted_by": null,
        "extracted_on": null,
        "verified_by": "OSMF research-tracker (web-verified against source)",
        "verified_on": "2026-07-21",
        "extraction_method": "manual"
      }
    },
    {
      "id": "recover-design-specimens",
      "cohort_id": "recover-adult-long-covid",
      "publication_id": "recover-horwitz-2023-design",
      "schema_version": "2.0.0",
      "measure_id": "sym:fatigue",
      "measure_verbatim": "Biospecimen banking: acute and convalescent serum, plasma, PBMC, whole blood, urine, saliva from all participants",
      "population": {
        "scope": "whole_cohort",
        "stratum": null,
        "denominator_basis": "assessed_at_timepoint",
        "n_assessed": { "status": "measured_not_reported" }
      },
      "timing": {
        "timepoint_months": 0,
        "timepoint_band": "acute",
        "reference_period": "not_reported",
        "is_cumulative": false
      },
      "method": {
        "ascertainment": "lab_assay",
        "instrument_id": null,
        "severity_threshold": null,
        "blinded_assessment": "not_applicable"
      },
      "value": {
        "type": "qualitative",
        "text": "Serum, plasma, PBMC, whole blood, urine, and saliva collected at enrolment and at scheduled follow-up visits from all ~15,000 participants. Acute-phase specimens available for those enrolled during acute COVID. Specimens stored at centralised RECOVER biorepository across multiple academic medical centres. Available to external researchers via application to the RECOVER biospecimen access committee.",
        "n_supporting": 15000
      },
      "comparator": {
        "group": "none",
        "value": { "status": "not_applicable" },
        "effect": null
      },
      "harmonised": null,
      "provenance": {
        "source_locator": "Horwitz 2023, Methods (biospecimen collection protocol; specimens collected at enrolment and follow-up visits)",
        "extracted_by": null,
        "extracted_on": null,
        "verified_by": "OSMF research-tracker (web-verified against source)",
        "verified_on": "2026-07-21",
        "extraction_method": "manual"
      }
    },
    {
      "id": "recover-design-controlled",
      "cohort_id": "recover-adult-long-covid",
      "publication_id": "recover-horwitz-2023-design",
      "schema_version": "2.0.0",
      "measure_id": "func:any-persistent-symptom",
      "measure_verbatim": "Controlled design: SARS-CoV-2 positive vs. negative participants from same communities",
      "population": {
        "scope": "whole_cohort",
        "stratum": null,
        "denominator_basis": "assessed_at_timepoint",
        "n_assessed": 15000
      },
      "timing": {
        "timepoint_months": 0,
        "timepoint_band": "acute",
        "reference_period": "not_applicable",
        "is_cumulative": false
      },
      "method": {
        "ascertainment": "registry_linkage",
        "instrument_id": null,
        "severity_threshold": null,
        "blinded_assessment": "not_applicable"
      },
      "value": {
        "type": "qualitative",
        "text": "RECOVER is the only Long COVID cohort with a national US sampling frame, SARS-CoV-2 negative controls drawn from the same communities, standardised multi-site protocol, acute-phase biospecimens, and 4-year planned follow-up. This makes it the Tier-1 reference cohort for Long COVID.",
        "n_supporting": 15000
      },
      "comparator": {
        "group": "unexposed_unmatched",
        "value": { "status": "measured_not_reported" },
        "effect": null
      },
      "harmonised": null,
      "provenance": {
        "source_locator": "Horwitz 2023, Methods (SARS-CoV-2 positive and negative participants enrolled from same catchment areas)",
        "extracted_by": null,
        "extracted_on": null,
        "verified_by": "OSMF research-tracker (web-verified against source)",
        "verified_on": "2026-07-21",
        "extraction_method": "manual"
      }
    }
  ],
  "estimates_status": "none"
}