Table 2.

Differences in autistic and ADHD traits between index twins with either a female or a male co-twin

		Female co-twin		Male co-twin
	Index twin	N	Mean rank	N	Mean rank	Mann–Whitney U	P	r
ADHD traits	Female	1793	3063	4195	2961	3,626,673	0.03	0.03
	Male	4190	3179	2109	3091	4,295,000	0.06	0.02
Autistic traits	Female	1795	3099	4197	2953	3,582,249	0.001	0.04
	Male	4197	3160	2115	3150	4,425,446	0.8	–

ADHD and autistic traits measured by the Autism—Tics, AD/HD, and other Comorbidities inventory (A-TAC). r effect size