Study variable definition

Clinical concept → operational definition → source fields and algorithms → derived variable

Flow diagram

Study variable definitionStudy variable definitionF1.S1Clinical concept and intended useF1.S2Operational definitionF1.S3Source fields and code listsF1.S4Derivation and missing-value rulesF1.S5Validation and adjudicationF1.S6Versioned study variableF1.N1Variable derivation dictionaryVariableSourcefieldCode listRuleUnitMissingruleVersionVariableF1.N2Measurement validation

Steps

Clinical concept and intended use

State the outcome, exposure, confounder or other construct.

Operational definition

Define units, coding, thresholds, time windows and eligibility for measurement.

Source fields and code lists

Identify source tables, vocabularies and code-list versions.

Derivation and missing-value rules

Specify priority, aggregation and missingness handling without converting unknowns to absence.

Validation and adjudication

Assess agreement, review ambiguous cases and refine definitions.

Versioned study variable

Record approved definition, code version and source lineage.

Tables and supporting information

Variable derivation dictionary

Variable derivation dictionaryVariableSourcefieldCode listRuleUnitMissingruleVersionVariable

Use separate rows for distinct variables and versions.

Measurement validation

Record validation dataset, reference standard and limitations.

Sources