A 7-page descriptive policy brief from the Center on Budget and Policy Priorities (CBPP) showing that four demographic and economic factors explain approximately 85% of cross-state variation in Disability Insurance/Supplemental Security Income (DI/SSI) receipt rates among the working-age population (ages 18–64, 2013 data): low educational attainment, older workforce, fewer immigrants, and blue-collar industry mix. The paper reframes the "geography of disability" — South and Appalachia rates nearly double the national average — as a structural consequence of the Social Security Administration's (SSA) own eligibility criteria operating on a labor force that is less educated, older, and more physically employed than the national average, not as evidence of program abuse or lax screening.
"Those four factors alone are associated with about 85 percent of the variation in disability receipt rates across states."
"A surgeon who suffers a stroke might become a pathologist or an insurance consultant, but that's hardly feasible for a 60-year-old waitress without a high-school diploma who has also suffered a stroke."
"Unemployment rates explain hardly any of the geographic variation. Although higher unemployment boosts disability applications, researchers conclude that those extra applicants are also more likely to be denied. The programs' eligibility rules are strict and don't become more lax in periods or areas of high unemployment."
The 85% claim comes from an OLS regression with four cross-state predictors — the causal logic is well-motivated by program rules but the analysis is purely correlational. The paper's framing is explicitly defensive of the program against claims that geographic variation reflects lax screening; it is advocacy analysis, not econometrics. The most analytically solid point is that unemployment barely explains geographic variation, consistent with the research literature showing that cyclical application surges don't translate into award surges. The surgeon-vs.-waitress example is an effective illustration of why SSA's vocational criteria mechanically produce the observed geographic distribution: less-educated workers with serious impairments have far fewer retraining options under the "any work in the national economy" standard, so their claims are more likely to be allowed at Step 5.