Each variable carries a stable id, allowed values, permitted provenance classes, a sensitivity class, whether it may ever appear in a public aggregate, and whether exact values must be binned. Free text is prohibited in every structured variable.
Demographics (broad, minimised)3
Chronology and trigger classes2
GI symptom domains3
Stool and motility pattern categories2
Autonomic symptom domains2
Exertional intolerance / PEM-like pattern flags2
Mast-cell / histamine-pattern domains2
Infection and post-infectious context1
Medication exposure categories1
Antibiotic and acid-suppression exposure2
Diet context categories1
Laboratory / test provenance1
Stool microbiome test categories2
Organic acids and metabolite categories2
Bile-acid categories1
Inflammatory and barrier markers2
Mitochondrial and metabolic markers1
Clinician-documented diagnoses (coded categories)1
Intervention exposure at class level1
Longitudinal observation timepoints2
Confidence and provenance grade1
Variable names encode provenance: reported_* is a self-reported pattern, recorded_* is transcribed from a source report, clinician_* requires clinician documentation. A reported pattern is never a diagnosis, and no marker listed is presented as a validated biomarker.