. Author manuscript; available in PMC: 2010 Aug 25.

Published in final edited form as: AJS. 2010 Mar;115(5):1387–1434. doi: 10.1086/651448

TABLE 7.

Effect of Proximity on the Likelihood of Subsequent Autism Diagnosis among Children Whose Nearest Neighbor with Autism Was from (A) the Same or (B) a Different School District

	(A) Same School District (N = 849,992)		(B) Different School District (N = 103,472)
	OR	95% CI	OR	95% CI
Proximity categories:
1–500 m	1.36^*	(1.14–1.62)	1.03	(.58–1.85)
501 m–1 km	1.00		1.00
1–2 km	.76^*	(.59–.98)	.79	(.45–1.38)
2–5 km	.66	(.42–1.04)	.39^*	(.16–.94)
Over 5 km	.33	(.08–1.34)	.31^*	(.12–.83)
Age:
2	.03^*	(.02–.05)	.07^*	(.02–.18)
3	1.00		1.00
4	.66^*	(.55–.80)	.83	(.50–1.38)
5	.41^*	(.30–.57)	.68	(.30–1.53)
6	.33^*	(.19–.56)	.24	(.03–1.76)
Year:
2000	1.00		1.00
2001	1.14	(.81–1.60)	1.58	(.68–3.67)
2002	1.42^*	(1.03–1.96)	1.23	(.50–3.01)
2003	1.25	(.90–1.73)	1.68	(.71–3.97)
2004	1.65^*	(1.20–2.27)	1.46	(.58–3.65)
2005	1.82^*	(1.33–2.50)	1.76	(.70–4.42)
Male	4.62^*	(3.79–5.64)	8.06^*	(4.03–16.11)
Mother’s years of education	1.08^*	(1.05–1.11)	1.12^*	(1.03–1.22)
Mother’s age at birth	1.07^*	(1.05–1.09)	1.07^*	(1.03–1.12)
Birth paid by Medi-Cal	.83	(.65–1.06)	.96	(.49–1.87)
Logged age 0–9 population density	1.11^*	(1.03–1.19)	1.19	(.95–1.49)
Logged median household income	.91	(.78–1.06)	.92	(.60–1.41)
Logged distance to nearest advocacy organization (reverse coded)	1.03	(.94–1.12)	1.17	(.91–1.51)
Logged distance to nearest DDS center (reverse coded)	1.08	(.98–1.19)	1.06	(.80–1.40)
Logged distance to nearest pediatrician (reverse coded)	1.01	(.93–1.10)	1.10	(.87–1.39)

Note.—All logged distances were reverse coded (i.e., 0 −ln(distance)). Larger values indicate closer proximity. Fifty-two percent of group A and 41% of group B lived in the high-population-density (top 50%) school districts.

P < .05.