Praxis Data Lab · Variable History
Variable history and harmonization report.
Review variable definitions, cycle chronology, survey design, laboratory methods, method-change boundaries, detection limits, and evidence-backed harmonization actions.
HistoryStart from an Explorer search
Search a concept or code first, then open its history report.
No variable scope selected
Search in Explorer before opening this report.
Examples: glucose, hemoglobin, blood pressure, depression, BMI, RXDDRUG.