Table 2 Comparison of study population and factor variables (n = 826) using a two-sample t-test
Variable | Maricopa County | Pima County | ||||||
|---|---|---|---|---|---|---|---|---|
Range | Median | Mean | SD | Range | Median | Mean | SD | |
Study population | 8–7105 | 364 | 507 | 611 | 7–1,930 | 262 | 352 | 306 |
Lower SES | −5.01 - 8.50 | −0.35 | 0.04 | 2.44 | −5.01 - 4.95 | −0.54 | −0.13 | 2.16 |
Increased air pollution*** | −10.0 - 17.0 | 1.62 | 2.05 | 4.85 | −12.3 - -0.75 | −6.84 | −6.88 | 2.52 |
Population density (persons/sq. mile)*** | 1.75–29,500 | 4900 | 5200 | 3300 | 3.08–9, 300 | 2920 | 3300 | 2400 |
Housing characteristics | ||||||||
 Mobile homes (%)*** | 0.00–86.8 | 0.60 | 4.86 | 11.1 | 0.00–76.8 | 1.40 | 10.1 | 19.2 |
 Attached homes (%)* | 0.00–98.6 | 22.5 | 26.9 | 24.0 | 0.00–80.7 | 19.7 | 22.3 | 20.6 |
 Home gas heating (%)*** | 0.00–100 | 25.2 | 27.3 | 18.5 | 10.5–88.1 | 59.2 | 57.4 | 16.0 |
 Lacking complete plumbing (%) | 0.00–13.4 | 0.00 | 0.36 | 1.06 | 0.00–3.40 | 0.00 | 0.41 | 0.75 |
 Built before 1940 (%)* | 0.00–73.4 | 0.00 | 1.53 | 5.61 | 0.00–58.1 | 0.30 | 2.84 | 7.78 |
  > 1 person per room (%)** | 0.00–60.0 | 2.70 | 5.54 | 7.15 | 0.00–22.5 | 1.55 | 3.77 | 5.17 |