NHANES (CDC), derived WHR percentiles
About this reference
NHANES collects waist circumference (BMXWAIST) and hip circumference (BMXHIP) in the same examination. FitnessNorms merged the August 2021-August 2023 body-measures and demographics files, retained adults aged 20 and older with positive measurements and MEC weight, excluded known pregnancies, calculated BMXWAIST divided by BMXHIP, and computed weighted empirical P5, P25, P50, P75, and P95 values in sex-specific 5-year age groups plus 80 and older. The final sample is 5,657 adults and the smallest cell contains 134 people. An earlier version pooled 2017-March 2020 with 2021-2023. Review corrected its common-divisor weighting to observation-period fractions of 3.2/5.2 and 2/5.2. The all-quantile sensitivity comparison found three female 20-24 differences greater than 0.02: P5, P50, and P75, with a maximum of 0.022. Because the latest release's cells remain above the 100-person review floor and avoid a cross-pandemic pool, the reviewed page uses August 2021-August 2023 alone. The period-adjusted pool remains a sensitivity artifact. The weighted quantile uses linear interpolation on the midpoint cumulative-weight positions. Survey weights are applied for point estimates, but strata, clusters, and survey-design standard errors are not estimated. These are transparent FitnessNorms derivations, not official CDC statistics.
Known limitations
- US civilian noninstitutionalised population only; percentile position may differ in populations with different body-size distributions.
- This is an internal derivation by FitnessNorms from CDC public microdata, not a peer-reviewed publication. Weighted empirical quantiles are used; survey-design-correct standard errors are not reported.
- The reviewed table uses one NHANES release. Its smallest sex-by-age cell contains 134 people, so tail percentiles are less stable than central percentiles.
- Known pregnancies reported in RIDEXPRG are excluded. Public pregnancy status is limited to women aged 20-44, although NHANES suppresses body measures for several known pregnant participants outside that range.
- The August 2021-August 2023 examination response rate was 25.6%; NCHS adjusted weights for nonresponse, but subgroup precision may be lower than in earlier cycles.
- Hip circumference was not measured in NHANES 2011-2016 cycles. Earlier data cannot be added to this latest-cycle reference without changing the evidence window.
- RIDAGEYR is top-coded at 80 in public data. The 80+ trend point at age 85 is a display anchor, not a mean observed age.
- NHANES measures waist at the iliac crest and hip at the maximum buttocks circumference. Values from other landmarks are not directly interchangeable with these percentiles or with protocol-specific guideline cut-offs.
- Cross-sectional design: values reflect population averages at the time of survey, not individual trajectories.