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.

1matching variable codes

12 release records across 12 datasets and 12 cycles.

Search scope

Results for “SDDSRVYR”

Harmonization summary

0 label-stable codes

Label changes detected
1
Multiple dataset contexts
0
Unique codes
1
Enriched codes in this report
0

Scientific safeguard

Qualified assessment is authoritative; chronology remains supporting evidence.

Praxis separates source-stated method or instrument changes from automated differences in CDC/NCHS method text. The qualified harmonization assessment below is the researcher-facing conclusion; method chronology explains the underlying evidence and does not override that adjudication.

Variable-by-variable chronology

Qualified harmonization assessment and indexed evidence

Each variable first shows the current qualified assessment used by Study Builder, followed by cycle-specific source evidence and method chronology.

SDDSRVYRCompatible with harmonization

Data Release Number.

Observed years
19992023
Release records
12
Datasets
12
Components
Demographics
Qualified Praxis harmonization assessment

Compatible with harmonization · moderate confidence

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

Relevant boundaries: 1999-2000 → 2001-2002 · 2001-2002 → 2003-2004 · 2003-2004 → 2005-2006 · 2005-2006 → 2007-2008 · 2007-2008 → 2009-2010 · 2009-2010 → 2011-2012 · 2011-2012 → 2013-2014 · 2013-2014 → 2015-2016 · 2015-2016 → 2017-2018 · 2017-2018 → 2017-2020 · 2017-2020 → 2021-2023

Praxis harmonization actions
  • Verify merge grain, companion variables, and component-specific analytic guidance for the new file context.
  • Select the weight appropriate to each cycle and subsample; when pooling cycles, construct the combined weight according to NHANES guidance rather than reusing a single-cycle weight unchanged.
  • Confirm that the construct and coding are unchanged before pooling or recoding.
Supporting CDC/NCHS evidence
Variable names / labels over time
  • Data Release Number.1999-2000 · 2001-2002 · 2003-2004 · 2005-2006 · 2007-2008 · 2009-2010
  • Data release cycle2011-2012 · 2013-2014 · 2015-2016 · 2017-2018 · 2017-2020 · 2021-2023
Cycle-by-cycle release history
  • 1999-2000: DEMO — Data Release Number. — Demographic Variables & Sample Weights (Demographics)
  • 2001-2002: DEMO_B — Data Release Number. — Demographic Variables & Sample Weights (Demographics)
  • 2003-2004: DEMO_C — Data Release Number. — Demographic Variables & Sample Weights (Demographics)
  • 2005-2006: DEMO_D — Data Release Number. — Demographic Variables & Sample Weights (Demographics)
  • 2007-2008: DEMO_E — Data Release Number. — Demographic Variables & Sample Weights (Demographics)
  • 2009-2010: DEMO_F — Data Release Number. — Demographic Variables & Sample Weights (Demographics)
  • 2011-2012: DEMO_G — Data release cycle — Demographic Variables & Sample Weights (Demographics)
  • 2013-2014: DEMO_H — Data release cycle — Demographic Variables and Sample Weights (Demographics)
  • 2015-2016: DEMO_I — Data release cycle — Demographic Variables and Sample Weights (Demographics)
  • 2017-2018: DEMO_J — Data release cycle — Demographic Variables and Sample Weights (Demographics)
  • 2017-2020: P_DEMO — Data release cycle — Demographic Variables and Sample Weights (Demographics)
  • 2021-2023: DEMO_L — Data release cycle — Demographic Variables and Sample Weights (Demographics)