RT Article T1 Childhood hyperactivity scores are highly heritable and show sibling competition effects: Twin study evidence JF Behavior genetics VO 25 IS 6 SP 537 OP 544 A1 Thapar, A. A1 Hervas, A. A1 McGuffin, P. LA English YR 1995 UL https://krimdok.uni-tuebingen.de/Record/1639390421 K1 Hyperaktivität K1 Zwillingsforschung