Data intelligence · automation · analyticsA Praxis Global Institute platform
Praxis Data Lab

Your Study Package

Review your Study Package before checkout.

This is the study you assembled. Confirm the selected variables, cycles, exact source files, automatic survey fields, and deliverables before proceeding to payment.

A research team reviewing results together around a laptop

Your specification

3 research variables · 1 cycle

Edit study
Complete the study specification first.
  • DSDFD1LC is not released for 1999-2000.
DCD030Room where samples taken
DCDINDEXLead - Dust
DSDFD1LCCat allergen Felis domesticus 1 (Fel d 1) dust allergen, comment code

Cycles: 1999-2000

Up to 50 researcher-selected variables per one-time package.

Source files for your study

Exact CDC/NCHS inputs selected for this specification

These are the source files Praxis will use for the variables and cycles shown above. They replace any generic sample-study file list.

  • DEMO.XPT · 1999-2000 — demographics, linkage, eligibility, weights and survey design
  • LAB20.XPT · 1999-2000 — selected variables: DCD030, DCDINDEX

Included automatically · no limit charge

Survey-ready foundations

  • SEQN participant identifier
  • NHANES cycle indicator
  • Eligibility fields
  • Appropriate sample weight
  • Survey strata
  • Survey PSU

Complete delivery

Reproducible files, not just a data export

  • Cleaned CSV, Parquet, and Excel outputs
  • Original CDC/NCHS source files and checksums
  • Codebook, harmonization record, and provenance
  • README, validation summary, and analysis specification
  • R and Python starter code

Preparation normally takes 5–10 minutes; please allow up to 15 minutes. You can leave after payment and return through My Study Packages, and we’ll email your secure download link when it is ready.