Table 3.

The Results of Multivariate Regression Analysis

Variables
Model 1A	B	Std.error	Beta	P value
Non-chronic
TP rest session 1	<0.001	0.000	0.002	0.995
Chronic
TP rest session 1	<0.001	0.000	−0.77	<0.001*
Overall
TP rest session 1	<0.001	0.000	−0.331	0.065
Model 1B	B	Std.error	Beta	P value
Non-chronic
TP rest session 1	<0.001	0.000	−0.197	0.518
Sex	1.931	1.047	0.542	0.095
Chronic
TP rest session 1	<0.001	0.000	−0.798	<0.001*
Sex	−0.253	0.259	−0.154	0.342
Overall
TP rest session 1	<0.001	0.000	−0.328	0.071
Sex	0.188	0.454	0.072	0.682
Model 2A	B	Std.error	Beta	P value
Non-chronic
LF/HF cold session 1	0.666	0.768	0.253	0.866
Chronic
LF/HF cold session 1	−0.489	0.123	−0.694	<0.001*
Overall
LF/HF cold session 1	0.019	0.222	0.015	0.085
Model 2B	B	Std.error	Beta	P value
Non-chronic
LF/HF cold session 1	0.698	0.702	0.265	0.343
Sex	1.699	0.95	0.476	0.104
Chronic
LF/HF cold session 1	−0.491	0.127	−0.697	0.001*
Sex	0.058	0.295	0.035	0.847
Overall
LF/HF cold session 1	0.036	0.227	0.029	0.876
Sex	0.232	0.486	0.089	0.637

Notes: Significantly correlated factors in the non-chronic and chronic pain groups and whole samples were examined using multivariate regression analysis. Model “A” only analyzed statistically correlated variables in Spearman’s rho correlation, and Model “B” included Model “A” with sex to adjust the imbalance in the groups’ sex ratios. *P<0.05.

Abbreviations: HF, high frequency, LF, low frequency; Std. error, Standard error; TP, total power.