Comparison of small-area deprivation measures as predictors of chronic disease burden in a low-income population.
BACKGROUND
Measures of small-area deprivation may be valuable in geographically targeting limited resources to prevent, diagnose, and effectively manage chronic conditions in vulnerable populations. We developed a census-based small-area socioeconomic deprivation index specifically to predict chronic disease burden among publically insured Medicaid recipients in South Carolina, a relatively poor state in the southern United States. We compared the predictive ability of the new index with that of four other small-area deprivation indicators.


METHODS
To derive the ZIP Code Tabulation Area-Level Palmetto Small-Area Deprivation Index (Palmetto SADI), we evaluated ten census variables across five socioeconomic deprivation domains, identifying the combination of census indicators most highly correlated with a set of five chronic disease conditions among South Carolina Medicaid enrollees. In separate validation studies, we used both logistic and spatial regression methods to assess the ability of Palmetto SADI to predict chronic disease burden among state Medicaid recipients relative to four alternative small-area socioeconomic deprivation measures: the Townsend index of material deprivation; a single-variable poverty indicator; and two small-area designations of health care resource deprivation, Primary Care Health Professional Shortage Area and Medically Underserved Area/Medically Underserved Population.


RESULTS
Palmetto SADI was the best predictor of chronic disease burden (presence of at least one condition and presence of two or more conditions) among state Medicaid recipients compared to all alternative deprivation measures tested.


CONCLUSIONS
A low-cost, regionally optimized socioeconomic deprivation index, Palmetto SADI can be used to identify areas in South Carolina at high risk for chronic disease burden among Medicaid recipients and other low-income Medicaid-eligible populations for targeted prevention, screening, diagnosis, disease self-management, and care coordination activities.
Institute for Families in Society, University of South Carolina, 1600 Hampton Street, Suite 507, Columbia, 29208, SC, USA. adefede@mailbox.sc.edu.
Ana
A
Lòpez-De Fede
Institute for Families in Society, University of South Carolina, 1600 Hampton Street, Suite 507, Columbia, 29208, SC, USA.
John E
JE
Stewart
Institute for Families in Society, University of South Carolina, 1600 Hampton Street, Suite 507, Columbia, 29208, SC, USA.|Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, 915 Greene Street, Room 445, Columbia, SC, USA.
James W
JW
Hardin
Institute for Families in Society, University of South Carolina, 1600 Hampton Street, Suite 507, Columbia, 29208, SC, USA.
Kathy
K
Mayfield-Smith
D002908:Chronic Disease / Q000453:epidemiology* / Q000628:therapy*; D017281:Cost of Illness; D005843:Geography; D006801:Humans; D011203:Poverty / Q000706:statistics & numerical data*; D012923:Social Class; D013022:South Carolina
Chronic disease; Low-income population; Small-area deprivation