CITF SARS-CoV-2 Serology Harmonization Protocol

The repository also includes the CITF serology Core Data Element schema and supporting serological assay metadata. The reporting guide is included as source-data reporting guidance used by contributing studies. Dataset structure The harmonized serology dataset is organized at the result level.

Each record represents one assay result for one participant. A participant may therefore have multiple records corresponding to different specimens, assays, or time points. The target schema includes participant, specimen, and assay identifiers; specimen and assay characteristics; specimen-collection and assay dates; units of measurement; quantitative results; standardized binding antibody units where available; qualitative interpretations; assay measurement limits; and result-level quality-control indicators.

Harmonization and quality control During harmonization, study-specific serology variables are mapped to the standardized CITF schema. Records are linked to standardized assay metadata using the CITF assay identifier. Quality-control procedures include: validation of participant, specimen, and assay identifiers; standardization and validation of dates, units, and categorical values; review of assay metadata; assessment of quantitative ranges; duplicate-record detection; and evaluation of internal consistency.

These procedures constitute dataset-level harmonization and quality control. They do not represent laboratory re-testing or independent biological validation of assay performance. Scope limitations Cell-mediated immunity data are outside the scope of this protocol and are not included in the harmonized serology dataset for Release v1.0.

Neutralizing-antibody variables are also excluded from the harmonized dataset for this release. Data access Individual-level serology data are held under controlled access and are not included in this repository. Access to restricted data requires a formal request to the CITF Data Access Office and is subject to applicable institutional approvals, consent conditions, governance requirements, and data-sharing agreements.

Protocol version: 2.8 Databank release: v1.0 Release date: February 2026