Table 3.

Multiple linear regression: tDCS predicting pain, disability, and quality of life

Dependent Variable	Independent Variable	B (Unstandardized Coef.)	SE (Standard Error)	95% CI	β (Standardized Coef.)	t-value	p-value	R²
NPRS (Pain Score)	tDCS Sessions	-0.27	0.09	-0.45 to -0.09	-0.36	-2.98	0.004	0.17
KOOS-PS (Physical Function)	tDCS Sessions	1.82	0.61	0.61 to 3.03	0.33	2.97	0.005	0.15
EQ-5D-5 L (Quality of Life)	tDCS Sessions	0.04	0.01	0.02 to 0.06	0.42	3.54	0.001	0.22

tDCS = Transcranial Direct Current Stimulation; NPRS = Numeric Pain Rating Scale; KOOS-PS = Knee Injury and Osteoarthritis Outcome Score– Physical Function Shortform; EQ-5D-5 L = EuroQol 5-Dimensions 5-Levels; B = Unstandardized Coefficient; SE = Standard Error; CI = Confidence Interval; β = Standardized Coefficient; R² = Coefficient of Determination