Table 1.
Prevalence of Medicaid-enrolled children with autism by county characteristics (n = 3,124 counties)
| Prevalence per 100,000 | Unadjusted % change | p value | Adjusted % change | p value | ||
|---|---|---|---|---|---|---|
| Total | 70.1 | |||||
| Total expenditures per student | 1st quartile (2,094–7,886) | 66.2 | Ref | – | Ref | – |
| 2nd quartile (7,887–8,856) | 60.6 | −8.5 | 0.769 | −4.4 | 0.219 | |
| 3rd quartile (8,857–10,317) | 67.0 | 1.3 | 0.237 | −5.6 | 0.176 | |
| 4th quartile (10,318–10,750) | 81.0 | 22.5 | 0.048 | −11.2 | 0.026 | |
| Proportion of students in special education | 1st quartile (0–0.122) | 58.1 | Ref | – | Ref | – |
| 2nd quartile (0.122–0.145) | 79.6 | 37.0 | 0.095 | 4.5 | 0.230 | |
| 3rd quartile (0.145–0.168) | 72.8 | 25.4 | 0.002 | 9.3 | 0.027 | |
| 4th quartile (0.168–0.680) | 77.2 | 32.9 | 0.006 | 8.0 | 0.100 | |
| Pupil/teacher ratio | 1st quartile (4.1–12.6) | 94.7 | Ref | – | Ref | – |
| 2nd quartile (12.7–14.3) | 66.5 | −29.8 | 0.963 | −2.9 | 0.511 | |
| 3rd quartile (14.4–15.8) | 75.3 | −20.5 | 0.231 | −2.3 | 0.657 | |
| 4th quartile (15.9–28.6) | 66.0 | −30.3 | 0.883 | −4.6 | 0.451 | |
| Per capita pediatricians (per 1,000) | None (0) | 69.6 | Ref | – | Ref | – |
| Low (0.03–0.32) | 75.3 | 8.1 | 0.003 | 5.2 | 0.199 | |
| High (0.321–5.35) | 68.8 | −1.2 | < 0.001 | 15.1 | 0.001 | |
| Per capita pediatric specialists (per 1,000) | None (0) | 74.1 | Ref | – | Ref | – |
| Any (0.02–35.84) | 69.6 | −6.1 | 0.003 | 8.9 | 0.024 | |
| Medicaid-enrolled population 0-21 years/Total Population | 1st quartile (0.027–0.265) | 50.1 | Ref | – | Ref | – |
| 2nd quartile (0.265–0.364) | 66.7 | 33.0 | < 0.001 | 25.1 | < 0.001 | |
| 3rd quartile (0.364–0.478) | 88.1 | 75.7 | < 0.001 | 48.4 | < 0.001 | |
| 4th quartile(0.478–0.956) | 74.6 | 48.9 | < 0.001 | 57.1 | < 0.001 | |
| In poverty (%) | 1st quartile (2.3–9.7) | 55.4 | Ref | – | Ref | – |
| 2nd quartile (9.8–12.7) | 76.3 | 37.8 | < 0.001 | 3.8 | 0.401 | |
| 3rd quartile (12.8–16.6) | 68.0 | 22.7 | < 0.001 | −1.6 | 0.789 | |
| 4th quartile (16.7–49.1) | 89.5 | 61.6 | < 0.001 | 13.5 | 0.117 | |
| Median income ($) | 1st quartile (16,610–29,618) | 78.6 | Ref | – | Ref | – |
| 2nd quartile (29,619–34,216) | 81.9 | 4.2 | 0.4872 | 2.6 | 0.598 | |
| 3rd quartile (34,233–39,907) | 97.8 | 24.4 | 0.5810 | 9.5 | 0.131 | |
| 4th quartile (39,928–93,927) | 56.4 | −28.2 | < 0.001 | −1.8 | 0.813 | |
| White (%) | 1st quartile (4.51–76.87) | 67.8 | Ref | – | Ref | – |
| 2nd quartile (76.90–91.16) | 58.0 | −14.5 | 0.995 | 8.9 | 0.023 | |
| 3rd quartile (91.19–96.68) | 87.0 | 28.3 | 0.173 | 22.2 | < 0.001 | |
| 4th quartile (96.70–99.74) | 111.8 | 64.8 | 0.150 | 27.1 | < 0.001 | |
| Total number of students ≤12th grade (1,000s) | 1st quartile (0.01–1.85) | 63.4 | Ref | – | Ref | – |
| 2nd quartile (1.85–4.27) | 74.9 | 16.2 | 0.005 | 9.3 | 0.077 | |
| 3rd quartile (4.27–10.58) | 85.5 | 32.6 | < 0.001 | 13.5 | 0.029 | |
| 4th quartile (10.59–1,706.00) | 67.9 | 5.4 | < 0.001 | 12.9 | 0.082 |