. Author manuscript; available in PMC: 2011 Oct 1.

Published in final edited form as: Pediatrics. 2010 Sep 27;126(4):e788–e795. doi: 10.1542/peds.2010-1187

TABLE 4.

Risk of RD^a Associated with ADHD, Separately by Gender

	N	Number of RD cases by age 19	Cumulative incidence by age 19, % (95%CI)	Unadjusted HR^b (95% CI), P-value	Adjusted HR^c (95% CI), P-value
Boys
ADHD	284	137	51.0 (44.5–56.6)	4.27 (3.50–5.21), <0.001	3.94 (3.19–4.85), <0.001
Non-ADHD	2666	332	14.5 (13.0–15.9)	1.00	1.00
Girls
ADHD	95	43	46.7 (35.5–56.0)	7.73 (5.54–10.80),<0.001	8.13 (5.73–11.54),<0.001
Non-ADHD	2654	176	7.7 (6.6–8.8)	1.00	1.00

HR, hazard ratio for ADHD vs. Non-ADHD.

RD, reading disability as determined by any of the three formulas.

^b,c

There is a statistically significant difference between the HR (for ADHD vs. non-ADHD) among boys and that among girls (P = 0.003 in the unadjusted model and P = 0.001 in the adjusted model).

Adjusted for children’s race (white v. non-white), mother’s educational level (four categories) and mother’s age at birth of child.