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Praxis Data Lab

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

ACD010B
Compatible with harmonizationmoderate confidence

Questionnaire

What language(s) {do you/does SP} usually speak at home?

Source releases
7
Available cycles
1999-2000 · 2001-2002 · 2003-2004 · 2005-2006 · 2007-2008 · 2009-2010 · 2021-2023
Dataset
Acculturation

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 · 2003-2004 → 2005-2006 · 2005-2006 → 2007-2008 · 2007-2008 → 2009-2010 · 2009-2010 → 2021-2023

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.
  • Confirm that the construct and coding are unchanged before pooling or recoding.
Supporting CDC/NCHS evidence
Remove from studyVariable historyCDC source
RIDAGEYR
Compatible with harmonizationhigh confidence

Demographics

Best age in years of the sample person at time of HH screening. Individuals 85 and over are topcoded at 85 years of age.

Source releases
13
Available cycles
1999-2000 · 2001-2002 · 2003-2004 · 2005-2006 · 2007-2008 · 2009-2010 · 2009-2010 · 2011-2012 · 2013-2014 · 2015-2016 · 2017-2018 · 2017-2020 · 2021-2023
Dataset
Demographic Variables & Sample Weights

RIDAGEYR remains age in years at screening, but CDC/NCHS changed the public-use disclosure top-code from 85 years and older through 2005-2006 to 80 years and older beginning in 2007-2008. The construct is continuous, but exact values in the oldest ages are not directly comparable across that disclosure boundary.

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

Evidence signals: source-stated

Relevant boundaries: 2005-2006 → 2007-2008

Praxis harmonization actions
  • For pooled analyses spanning the 2005-2006 to 2007-2008 boundary, harmonize the upper age range to a common 80+ category or restrict continuous-age analyses to participants younger than 80. Do not treat published top-coded values as exact ages.
Supporting CDC/NCHS evidence
Remove from studyVariable historyCDC source