Baseline Characteristics of the Study Populations, 2009
| Characteristic | Group Health Practices (n=305,578) | Network Practices (n=107,365) | Total (N=412,943) |
|---|---|---|---|
| Age, mean (SD), y | 43.5 (22.6) | 40.4 (21.9) | 42.7 (22.5) |
| Age-group, No. (%) | |||
| 1–5 years | 12,889 (4.2) | 5,104 (4.9) | 17,993 (4.4) |
| 6–11 years | 18,307 (5.9) | 8,050 (7.7) | 26,357 (6.4) |
| 12–16 years | 19,156 (6.2) | 8,283 (7.9) | 27,439 (6.6) |
| 17–34 years | 57,226 (18.5) | 18,328 (17.5) | 75,554 (18.3) |
| 35–44 years | 37,959 (12.3) | 13,556 (13.0) | 51,525 (12.5) |
| 45–64 years | 109,707 (35.6) | 38,753 (37.1) | 148,461 (36.0) |
| 65–74 years | 26,836 (8.7) | 6,644 (6.4) | 33,480 (8.1) |
| 75–84 years | 17,860 (5.8) | 4,300 (4.1) | 22,160 (5.4) |
| ≥85 years | 8,563 (2.8) | 1,411 (1.4) | 9,974 (2.4) |
| Education, neighborhood level, No. (%) | |||
| High | 13,679 (40.1) | 37,118 (35.5) | 160,797 (39.0) |
| Medium | 152,462 (49.4) | 53,327 (51.1) | 205,789 (49.8) |
| Low | 32,331 (10.5) | 13,985 (13.4) | 46,316 (11.2) |
| Family income, neighborhood level, median (SD), $ | 59,882 (19,833) | 51,909 (15,122) | 57,787 (19,037) |
| Residence location, RUCA, No. (%) | |||
| Urban | 269,515 (96.1) | 75,241 (72.0) | 371,756 (90.0) |
| Metropolitan/large rural | 5,868 (1.9) | 19,598 (18.8) | 25,466 (6.2) |
| Small rural/isolated areas | 2,811 (0.9) | 7,472 (7.2) | 10,283 (2.5) |
| Not mapped | 3,309 (1.1) | 2,129 (2.0) | 5,438 (1.3) |
| Insurance segment, No. (%) | |||
| Medicare | 55,435 (18.0) | 13,038 (12.5) | 68,473 (16.6) |
| Medicaid | 9,196 (3.0) | 838 (0.8) | 10,034 (2.4) |
| Commercial/self-pay | 221,190 (71.7) | 86,904 (83.2) | 308,064 (74.6) |
| Individual or family plan | 22,682 (7.4) | 3,660 (3.5) | 26,342 (6.4) |
| Health plan product, No. (%) | |||
| HMO | 257,466 (83.5) | 73,383 (70.3) | 330,849 (80.1) |
| PPO/POS | 51,037 (16.5) | 31,057 (29.7) | 82,094 (19.9) |
| Insurance benefit design, No. (%) | |||
| Well-care waiver | 203,166 (66.0) | 65,949 (63.0) | 269,115 (65.2) |
| High-deductible plan | 3,157 (1.0) | 997 (1.0) | 4,154 (1.0) |
| Drug coverage | 267,857 (87.0) | 95,880 (92.0) | 363,737 (88.1) |
| Morbidity, ACG RUB category, No. (%) | |||
| 0 (nonusers) | 37,417 (7.1) | 11,134 (6.0) | 48,551 (6.8) |
| 1 (low morbidity) | 36,332 (6.9) | 12,414 (6.7) | 48,746 (6.8) |
| 2 | 53,530 (10.1) | 19,901 (10.7) | 73,431 (10.3) |
| 3 | 133,188 (25.2) | 45,905 (24.8) | 179,093 (25.1) |
| 4 | 31,992 (6.0) | 10,613 (5.7) | 42,535 (6.0) |
| 5 (high morbidity) | 14,142 (2.7) | 4,026 (2.2) | 18,168 (2.5) |
HMO = health maintenance organization; POS = point of service; PPO = preferred provider organization; ACG = adjusted clinical group; RUB = Resource Utilization Band; RUCA = rural urban commuting area.