Praxis Data Lab · Study Builder

Build your NHANES study with harmonization intelligence.

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.

2variables selected

Praxis harmonization guidance available

Praxis found harmonization conditions for this study and has surfaced them below with the supporting source evidence.

2 variable assessments

ALQ140U

Compatible with harmonizationmoderate confidence

Questionnaire

UNIT OF MEASURE.

Source releases: 6
Available cycles: 1999-2000 · 2001-2002 · 2003-2004 · 2005-2006 · 2007-2008 · 2009-2010
Dataset: Alcohol Use

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 · 2003-2004 → 2005-2006 · 2005-2006 → 2007-2008 · 2007-2008 → 2009-2010

Praxis harmonization actions

Apply cycle-specific eligibility rules and restrict the pooled analytic population to a defensible common target population.
Verify merge grain, companion variables, and component-specific analytic guidance for the new file context.

Supporting CDC/NCHS evidence

Remove from study Variable history CDC source

ARD026C

Evidence developinglow confidence

Questionnaire

How often did {you/SP} get MID BACK pain, aching or stiffness? Did {you/SP} have it…

Source releases: 1
Available cycles: 2009-2010
Dataset: Arthritis

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

Remove from study Variable history CDC source