Table 2.

Demographic Characteristics of Subjects by High- and Low-risk ZIP Code

Demographic CharacteristicLow-risk
ZIP Code
(n = 456)
High-risk
ZIP Code
(n = 282)
χ2
P value
Mean age, months (standard
 deviation)
15.2 (5.8)15.8 (6.4)NS
Male gender51%54%NS
Race/ethnicity n = 455 n = 277
 African-American4%27%<.001*
 Hispanic4%8%
 Non-Hispanic white85%57%
 Other7%8%
Insurance status n = 453 n = 276
 Private insurance73%34%<.001*
 Medicaid23%58%
 Not insured3%4%
 Other1%4%
Maternal education n = 448 n = 269
 Less than high school graduate11%26%<.001*
 High school graduate13%30%
 Some college30%27%
 College graduate46%17%
Rent home n = 450 n = 275
26%60%<.001
Year house built n = 456 n = 282
 Before 195018%16%<.001*
 1950–195912%10%
 1960 or later60%36%
 Don't know or missing10%38%
Enrolled at practice site76%39%<.001
  • * χ2 analysis includes 3 degrees of freedom.