Chronic fatigue is associated with increased disease-related worries and concerns in inflammatory bowel disease

Table 6 Linear regression analysιs of the rating form of inflammatory bowel disease patient concerns sum score, Norwegian inflammatory bowel disease questionnaire total score, total fatigue, chronic fatigue, Short Form 36 subdimensions and calculation of multicolinearity

Dependent		Independent	ß	P value	Tolerance	VIF
UC	RFIPC sum	N-IBDQ total	-0.70	< 0.001	0.24	4.1
	N-IBDQ total	RFIPC sum	0.29	< 0.001	0.58	1.7
		SF-36 BP	0.14	0.032	0.57	1.7
		SF-36 VT	0.17	0.019	0.50	2.0
		SF-36 SF	0.29	< 0.001	0.39	2.6
	TF	SF-36 VT	-0.25	0.031	0.49	2.0
	CF	RFIPC sum	0.34	0.018	0.46	2.2
CD	RFIPC sum	N-IBDQ total	-0.60	0.047	0.21	4.9
	N-IBDQ total	RFIPC sum	-0.17	0.047	0.71	1.4
		SF-36 SF	0.35	0.004	0.39	2.6
		SF-36 PF	0.22	0.033	0.49	2.0
		TF	-0.31	0.015	0.34	2.9

RFIPC: Rating form of inflammatory bowel disease patient concerns; CD: Crohn’s disease; UC: Ulcerative colitis; TF: Total fatigue; CF: Chronic fatigue; N-IBDQ: Norwegian inflammatory bowel disease questionnaire; SF-36: Short Form 36; PF: Physical functioning; BP: Bodily pain; VT: Vitality; SF: Social functioning; VIF: Variance inflation factor.