Examining impulsivity as an endophenotype using a behavioral approach: a DRD2 TaqI A and DRD4 48-bp VNTR association study

Table 4 Descriptive statistics

	N	Mean	Min	Max	SD
BIS Attentional Impulsivity	182	17.03	9	29	3.49
BIS Motor Impulsivity	185	21.68	13	34	3.73
BIS Non-planning Impulsivity	181	25.38	14	38	4.07
BIS Total	168	63.93	37	95	9.24
EIQ Ventursomeness	190	9.58	0	17	3.51
EIQ Impulsivity	182	10.11	0	22	4.44
SSS Disinhibition	185	5.63	0	10	2.53
SSS Experience Seeking	186	5.40	0	10	1.96
SSS Boredom Susceptibility	190	3.07	0	8	2.02
SSS Thrill & Adventure Seeking	190	6.48	0	10	2.75
SSS Total	179	20.57	6	34	6.09
DDT*	166	0.05	0.00	1.72	0.02–0.17

* untransformed DDT value with median and IQR given instead of Mean and SD
BIS = Barratt impulsivity Scale; EIQ = Eysenck Impulsivity Questionnaire; SSS = Sensation Seeking Scale; DDT = Delay Discounting Task.