Table 3.

Results of the regression analyses on peak negative and positive affect during the stress period

Dependent variable/independent variable	β	R2	T/F(6,114)	P
Negative affect
Entire model		0.28	7.28	0.001
Sexa	−0.121		−1.36	0.17
Age	−0.110		−1.31	0.19
BMI	−0.003		−0.33	0.97
Trait anger	0.145		1.17	0.25
Khat chewingb	−0.448		−1.36	0.18
Trait anger by khat chewing	0.829		2.32	0.02
Positive affect
Entire model		0.18	4.09	0.001
Sexa	0.218		1.69	0.09
Age	0.174		1.87	0.06
BMI	0.116		1.25	0.21
Trait anger	−0.016		−0.18	0.86
Khat chewingb	0.448		−1.75	0.08
Sex by khat chewing	0.225		0.57	0.57

^aSex: 1 = female; 2 = male.

^bKhat chewing: 1 = no; 2 = occasionally; 3 = regularly.