Table 6.

OR and 95% CI of ADHD associated with urinary BPA level

Tertile groups of urine BPA level	Number	Number of cases (%)	Crude modela		Adjusted model 1b		Adjusted model 2c
			OR	95% CI	OR	95% CI	OR	95% CI
All
Urinary BPA level (min, max) (ppb)
Q1 (0.11, 0.93)	148	55 (37.2)	1	Reference	1	Reference	1	Reference
Q2 (0.95, 2.01)	147	65 (44.2)	1.340	0.841−2.136	1.283	0.784−2.099	1.236	0.744−2.053
Q3 (2.05, 46.93)	149	75 (50.3)	1.714*	1.079−2.723	1.413	0.850−2.348	1.404	0.833−2.365
Boys
Urinary BPA level (min, max) (ppb)
Q1 (0.11, 0.93)	101	33 (32.7)	1	Reference	1	Reference	1	Reference
Q2 (0.95, 2.01)	97	48 (49.5)	2.019*	1.135−3.589	1.878*	1.040−3.392	1.808	0.985−3.318
Q3 (2.05, 46.93)	98	56 (57.1)	2.747**	1.543−4.893	2.216*	1.199−4.094	2.219*	1.131−4.006
Girls
Urinary BPA level (min, max) (ppb)
Q1 (0.11, 0.93)	47	22 (46.8)	1	Reference	1	Reference	1	Reference
Q2 (0.95, 2.01)	50	17 (34.0)	0.585	0.258−1.328	0.549	0.203−1.484	0.498	0.174−1.421
Q3 (2.05, 46.93)	51	19 (37.3)	0.675	0.301−1.511	0.483	0.176−1.323	0.480	0.170−1.360

OR, odds ratio; CI, confidence interval; ADHD, attention deficit hyperactivity disorder; BPA, bisphenol A.

^aOR and 95% CI estimated using logistic regression model referenced by the first quartile group of urinary BPA level. ^b OR and 95% CI estimated using logistic regression model referenced by the first quartile group of urinary BPA level adjusted for age, sex, paternal and maternal educational level, and household income level. ^c OR and 95% CI estimated using logistic regression model referenced by the first quartile group of urinary BPA level adjusted for age, sex, paternal and maternal educational level, household income level, and current exposure to secondhand smoke.

^*p < 0.05; ** p < 0.01.