Table 3.

Barratt Impulsiveness Scale (BIS-11) scores in subjects with bipolar disorder and in healthy comparison subjects

	Comparison (n = 70)	Bipolar disorder (n = 114)	t^a	Extrapolated to zero symptoms

				Comparison	Bipolar	t^b
Total	56.6 ± 8.8	80.3 ± 12.4	13.9	56.6 ± 1.6	75.1 ± 2.3	4.7
Nonplanning	21.4 ± 4.3	29.6 ± 5.7	10.7	21.2 ± 0.8	27.9 ± 1.3	3.3
Motor	21.5 ± 4.1	28.8 ± 5.3	10.1	21.6 ± 0.7	27.9 ± 1.2	3.2
Attentional	13.8 ± 3.5	21.8 ± 4.4	13.2	14.0 ± 0.6	19.2 ± 0.9	3.4

Means for BIS-11 total or component scores are given with standard deviations. Extrapolated values are y-intercepts calculated from multiple regression analyses, with BIS-11 score as dependent variable and depression, mania, anxiety, and psychosis scores as independent variables, as described in the text, and are given with standard error of the fit.

For all direct comparisons, p < 10⁻⁶.

For all comparisons of extrapolated values, p < 10⁻⁴.