Variability and vulnerability at the ecological level: implications for understanding the social determinants of health.
OBJECTIVE
We examined variability in disease rates to gain understanding of the complex interactions between contextual socioeconomic factors and health.


METHODS
We compared mortality rates between New York and California counties in the lowest and highest quartiles of socioeconomic status (SES), assessed rate variability between counties for various outcomes, and examined correlations between outcomes' sensitivity to SES and their variability.


RESULTS
Outcomes with mortality rates that differed most by county SES were among those whose variability across counties was high (e.g., AIDS, homicide, cirrhosis). Lower-SES counties manifested greater variability among outcome measures.


CONCLUSIONS
Differences in health outcome variability reflect differences in SES impact on health. Health variability at the ecological level might reflect the impact of stressors on vulnerable populations.
Karpati
Adam
A
Department of Population and International Health, Harvard School of Public Health, Boston, Mass, USA. aek3@cdc.gov
Galea
Sandro
S
Awerbuch
Tamara
T
Levins
Richard
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D002140:California / Q000453:epidemiology; D002423:Cause of Death; D002648:Child; D002675:Child, Preschool; D003627:Data Interpretation, Statistical; D004194:Disease / Q000145:classification / Q000191:economics; D004522:Educational Status; D006305:Health Status Indicators; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D009026:Mortality; D009518:New York / Q000453:epidemiology; D011203:Poverty / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D012923:Social Class; D012959:Socioeconomic Factors; D014478:Unemployment / Q000706:statistics & numerical data