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.

3variables selected
Praxis harmonization guidance available

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

3 variable assessments

AAXFLTYP
Evidence developinglow confidence

Laboratory

Type of Floor Covering

Source releases
1
Available cycles
2005-2006
Dataset
Allergens - Household Dust

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

ARXO2WD
Evidence developinglow confidence

Examination

OCCIPUT-TO-WALL DISTANCE IN CENTIMETERS

Source releases
1
Available cycles
2009-2010
Dataset
Arthritis Body Measures

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

RIAGENDR
Compatiblehigh confidence

Demographics

Gender of the sample person

Source releases
39
Available cycles
1999-2000 · 2001-2002 · 2001-2002 · 2001-2002 · 2001-2002 · 2003-2004 · 2005-2006 · 2005-2006 · 2005-2006 · 2005-2006 · 2005-2006 · 2007-2008 · 2007-2008 · 2007-2008 · 2007-2008 · 2007-2008 · 2009-2010 · 2009-2010 · 2009-2010 · 2009-2010 · 2009-2010 · 2011-2012 · 2011-2012 · 2011-2012 · 2011-2012 · 2011-2012 · 2013-2014 · 2013-2014 · 2013-2014 · 2013-2014 · 2013-2014 · 2015-2016 · 2015-2016 · 2015-2016 · 2015-2016 · 2015-2016 · 2017-2018 · 2017-2020 · 2021-2023
Dataset
Demographic Variables & Sample Weights

CDC/NCHS releases RIAGENDR consistently as the same two-category demographic variable across Continuous NHANES, with code 1 for Male and code 2 for Female. Indexed DEMO-file method, target, and weight changes do not by themselves establish a change in the variable's released coding or longitudinal construct.

Evidence provenance: CDC/NCHS source-confirmed evidence · Praxis deterministic adjudication

Evidence signals: source-stated

Praxis harmonization actions
  • Pool the released RIAGENDR categories directly across calibrated cycles. Apply cycle-appropriate NHANES survey weights and design variables separately, and do not reinterpret RIAGENDR as a gender-identity measure beyond the released CDC/NCHS coding.
Supporting CDC/NCHS evidence