Table 4.

Meta-analysis of studies examining the association between day-care attendance and risk of c-ALL

Study, year	Age	Day-care definition	Timing	Cases	OR	95% CI	Wi (%)a
Schuz et al., 199942	1.5–14	Deficit in social contacts: Yes/no	Before age 2 years	658	1.00	0.80, 1.20	19.9
Neglia et al., 200038	2–5	Day care before age 2 years: Yes/no	Before age 2 years	633	1.05	0.80, 1.37	16.3
Chan et al., 200232	2–14	Index and family day care: 3-level	First year of life	66	0.93	0.63, 1.36	11.4
Jourdan-Da Silva, 200435	1–14	Day-care attendance: Yes/no	Birth to dx	304	0.80	0.60, 1.00	17.0
Gilham et al., 200533	2–5	Social activity: Any/none	First year of life	791	0.67	0.55, 0.82	20.1
Ma et al., 2005—White37	2–5	Day care first year of life: Yes/no	First year of life	74	0.49	0.19, 1.26	2.8
—-Hispanic37,b	2–5	Day-care attendance: Yes/no	Birth to dx	71	0.91	0.41, 2.05	3.8
Kamper-Jorgensen et al., 200836	0–15	Attendance to child care: Yes/no	Before age 2 years	101	0.58	0.36, 0.93	8.7
	P-value (heterogeneity) = 0.044	Combined:	2698	0.83	0.70, 0.98	100.0

^aPercent weight assigned to each OR in the random effects model.

^bDay-care attendance censored on reference date was used due to the low number of Hispanic subjects attending day-care during the first year of life.

dx, diagnosis; Wi, weight.