Table 3.

Multiple regression model of fatigue (fVAS scores) and selected variables

Variables	Estimate	Std. error	P
Depression (BDI) scores	0.97	0.40	0.019
Pain (SF-36) scores*	0.38	0.13	0.004
IL-1Ra	0.54	0.19	0.009

Statistics for the final model: adjusted R² 0.37, P value < 0.001

Abbreviations: BDI Beck Depression Inventory, SF-36 36-item short form survey instrument, IL-1Ra interleukin 1 receptor antagonist

*SF-36 pain scores are reported according to the transformed scale with high scores indicating high bodily pain and low scores indicating low bodily pain