Methodology · component
Social Need / SDOH — how we measure it
One component of the ZipVitals Score. This page covers only this component — what it is built from, how those sources reach your ZIP, where they stop, and how it enters the composite. For the full recipe and the whole weight table, see the main methodology page.
Effective weight 0.1579 of the composite · higher = worse
Where this sits in the Score
The material conditions around health — income, housing cost, energy burden, and access to food and services — that shape outcomes long before anyone reaches a clinic.
Feeds domain
Social Need / SDOH
0.1579
effective weight · nominal 0.15 · higher = worse
Social Need / SDOH is 1 of 9 scoring domains. Life expectancy is held out of the composite as an independent validator, so the nine renormalize to sum to 1.00 and this domain’s share lands at 0.1579.
It is built from 5 sources, listed below with what each one contributes and what it cannot tell you.
The sources feeding Social Need / SDOH
Each source is labeled with what kind of number it is — observed, model-based, or administrative — because a modeled risk surface and a counted facility are not the same kind of fact. We name which is which.
CDC PLACES — health-related social needs
Model-basedCDC
CDC's health-related social-needs measures: food insecurity, housing insecurity, lack of reliable transport, social isolation and utility-shutoff risk.
The honest limit: Newer than the rest of PLACES and published for a narrower footprint — roughly 39 states and DC — so these measures are absent in more places than the chronic-disease set, and carry the same model-based-estimate caveat.
Census American Community Survey (5-year)
ObservedUS Census Bureau
Income and poverty, housing cost burden, vehicle access, educational attainment and health-insurance coverage.
The honest limit: A rolling five-year survey window, so it lags a sudden local change, and at ZIP scale the margin of error is real. A survey also reflects the people who answered it, and non-response is not random.
DOE LEAD — energy burden
Model-basedUS Department of Energy
Energy burden — the share of household income that goes to utility bills, the cost pressure that shows up as an unheated or uncooled home.
The honest limit: A modeled tract-level estimate built on survey inputs, not a reading of anyone’s bill. Four territories are left unavailable rather than filled in from a coarser geography.
HUD LIHTC — subsidized affordable housing
AdministrativeUS Department of Housing and Urban Development
The location and scale of federally subsidized affordable housing built under the Low-Income Housing Tax Credit.
The honest limit: A register of what was funded, so it reflects where subsidy was awarded rather than how much affordable housing a place needs. It carries roughly a two-year reporting lag.
NaNDA — neighborhood services and built environment
AdministrativeNational Neighborhood Data Archive (ICPSR, University of Michigan)
Density of the everyday infrastructure of a neighborhood — food outlets, pharmacies, social-service providers and similar.
The honest limit: Built from a commercial business register with a 2021 vintage, so a business that opened or closed since is not reflected. Several of its datasets carry a non-commercial license, disclosed wherever they surface.
How these reach your ZIP
Every value is a fact about the ZIP itself. A source that is not published at ZIP level is rolled up against a published Census boundary file, weighted by population or land area as appropriate — never inherited from the county or state and rebranded as the ZIP’s. Where a legitimate ZIP value cannot be produced, the metric is shown as unavailable.
- CDC PLACES — health-related social needs
- Published by CDC at ZIP level. No rollup of ours is involved.
- Census American Community Survey (5-year)
- Published by the Census Bureau at ZIP level.
- DOE LEAD — energy burden
- Census tract → ZIP, population-weighted.
- HUD LIHTC — subsidized affordable housing
- Property locations, matched to the ZIP that contains them.
- NaNDA — neighborhood services and built environment
- Published at ZIP level.
Coverage & limitations — for this component
This is the honest part. Every limit below is a published, named limit of this component specifically, so you can judge how far to trust one of its numbers. We treat limitations as a trust signal, not fine print.
Where this component’s data stops
No limit is published for this component beyond the ones that apply site-wide — the reliability floor that suppresses rates built on too few people, the restricted coverage in US territories, and each source’s own limit stated above. That is not a claim of completeness: it means this component has no additional named gap in the coverage register.
How it enters the Score
Every metric in this component goes through the same pipeline as the rest of the Score, then contributes to the Social Need / SDOH sub-score — which contributes its 0.1579 to the composite.
- Standardize. Each metric becomes a z-score against the national distribution of ZIP codes, so a concentration, a rate and a distance become comparable.
- Cap outliers. Each z-score is capped, so one extreme ZIP cannot dominate the scale.
- Build the sub-score. The capped metrics combine into the Social Need / SDOH sub-score, weighted by source and then equally within a source — so a source that publishes many metrics cannot swamp one that publishes few.
- Weight into the composite. Social Need / SDOH contributes 0.1579 to the domain-weighted sum, which is rescaled to the 0–100 Score.
Go deeper
This is one component of the method. Follow any of these for the whole picture, or for this component in context.