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.

2matching variable codes

10 release records across 10 datasets and 10 cycles.

Search scope

Results for “DR1_320”

Harmonization summary

2 label-stable codes

Label changes detected
0
Multiple dataset contexts
0
Unique codes
2
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.

DR1_320Evidence developing

Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water.

Observed years
20032004
Release records
1
Datasets
1
Components
Dietary
Qualified Praxis harmonization assessment

Evidence developing · low confidence

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

Variable names / labels over time
  • Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water.2003-2004
Cycle-by-cycle release history
  • 2003-2004: DR1TOT_C — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
DR1_320ZCompatible with harmonization

Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water.

Observed years
20052023
Release records
9
Datasets
9
Components
Dietary
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: 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.
  • Review the adjacent codebooks/methods. Keep this boundary as documentation variation unless source evidence confirms a substantive method or instrument change.
  • 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.
Supporting CDC/NCHS evidence
Variable names / labels over time
  • Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water.2005-2006 · 2007-2008 · 2009-2010 · 2011-2012 · 2013-2014 · 2015-2016 · 2017-2018 · 2017-2020 · 2021-2023
Cycle-by-cycle release history
  • 2005-2006: DR1TOT_D — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2007-2008: DR1TOT_E — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2009-2010: DR1TOT_F — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2011-2012: DR1TOT_G — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2013-2014: DR1TOT_H — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2015-2016: DR1TOT_I — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2017-2018: DR1TOT_J — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2017-2020: P_DR1TOT — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)
  • 2021-2023: DR1TOT_L — Total plain water drank yesterday - including plain tap water, water from a drinking fountain, water from a water cooler, bottled water, and spring water. — Dietary Interview - Total Nutrient Intakes, First Day (Dietary)