Table 3.

Sex, changes in daily events, and their interaction in the prediction of same-day fatigue.

Predictor Variables	β	t	Probability
Female	4.30	1.75	.09
Co-morbid Pain Condition	11.82	5.21	<.0001
Δ Pain	0.47	20.74	<.0001
Δ Positive Events	−0.13	−0.90	.37
Δ Negative Events	0.44	3.12	.002
Δ Positive Events × Female	−0.36	−2.01	.05

Note: Pain and event scores are person-centered. Pain and interaction terms were modeled as random effects. Fatigue was significantly higher in individuals with a co-morbid pain condition relative to those without one. Fatigue was also higher for individuals on days when they experienced greater than their average number of negative events, and lower on days when they experienced greater than their average number of positive events. The relation between positive events and fatigue was stronger in women than in men.