Praxis Data Lab · Study Builder
Combine variables from the indexed Continuous NHANES catalog, choose the cycles you need, and see how Praxis connects source history, methods, cycle boundaries, and cross-code lineage into a study-specific harmonization view.
Praxis found harmonization conditions for this study and has surfaced them below with the supporting source evidence.
5 variable assessments
Laboratory
No normalized longitudinal change evidence is available for this variable. Absence of events must not be interpreted as proof of cross-cycle equivalence.
Evidence provenance: Praxis automated inference from indexed CDC/NCHS evidence
Questionnaire
No blocking method discontinuity is identified inside the selected cycle span, but one or more longitudinal changes require explicit harmonization conditions before pooling.
Evidence provenance: Praxis automated inference from indexed CDC/NCHS evidence
Evidence signals: source-derived
Relevant boundaries: 1999-2000 → 2001-2002 · 2001-2002 → 2003-2004
Examination
No normalized longitudinal change evidence is available for this variable. Absence of events must not be interpreted as proof of cross-cycle equivalence.
Evidence provenance: Praxis automated inference from indexed CDC/NCHS evidence
Examination
CDC/NCHS documentation supports continuity of the core NHANES anthropometry protocol across Continuous NHANES. Indexed differences for standing height are limited to dataset context and documentation wording, not a confirmed measurement discontinuity.
Evidence provenance: CDC/NCHS source-confirmed evidence · Praxis deterministic adjudication
Evidence signals: source-stated
Laboratory
No blocking method discontinuity is identified inside the selected cycle span, but one or more longitudinal changes require explicit harmonization conditions before pooling.
Evidence provenance: Praxis automated inference from indexed CDC/NCHS evidence
Evidence signals: source-derived · automated-difference
Relevant boundaries: 1999-2000 → 2001-2002 · 2001-2002 → 2003-2004