Praxis Data Lab · Validation Record 001

Evidence that can be inspected, not merely asserted.

Praxis reproduced an authoritative NCHS analytical result using the documented NHANES population, variables, eligibility rules, survey design, and examination weights.

Authoritative comparison

Depression prevalence among U.S. adults aged 20 and over, 2013–2016

NCHS published estimate8.1%

Data Brief No. 303

Praxis reproduced estimate8.1%

At the published precision

Observed difference0.043 pp

Percentage points

Acceptance tolerance±0.05 pp

Rounding-equivalent boundary

The authoritative NCHS result is published to one decimal place; ±0.05 percentage points is the rounding-equivalent acceptance boundary.

Reproducible method

What the test reruns

Population: U.S. civilian noninstitutionalized adults aged 20 and over with a valid PHQ-9 depression score
Survey cycles: 2013–2014 and 2015–2016
Variables: SEQN, RIDAGEYR, DPQ010–DPQ090, WTMEC2YR, SDMVSTRA, SDMVPSU
Outcome: PHQ-9 score of 10 or higher
Participant linkage: SEQN
Weight: WTMEC2YR divided by 2 to create a four-year MEC examination weight
Survey design: Taylor-series survey estimation using SDMVSTRA and SDMVPSU with nesting enabled
Missing responses: Responses coded 7 (Refused) or 9 (Don't know) are excluded before the nine-item score is calculated.

Interpretation boundary

One exact benchmark. A foundation for a broader suite.

This record validates the analysis shown here and establishes the automated pathway for future benchmarks. It does not mean that every NHANES variable has been independently benchmarked.

Praxis independently reproduced this benchmark against public CDC/NCHS evidence. CDC/NCHS has not certified or endorsed Praxis Data Lab.

Read the full research-use notice