Table 3. Logistic Regression Analysis of the relationship between the likelihood of postoperative complications based on treatment with or without HBOT and the amount of radiation damage. a − variables entered on step 1 were HBOT, radiation damage; Beta − coefficient for the constant (intercept); CI = confidence interval; df − degrees of freedom for the Wald Chi-Square test; Exp (β) − exponentiation of the β coefficient (odds ratio); SE − standard error; Wald − Wald Chi-Square that tests the null hypothesis that the constant equals 0 .

Variables in the equation		Beta	SE	Wald	df	P	Exp (beta)	95% CI for Exp (beta)
								Lower	Upper
Step 1a	HBOT	-0.362	0.890	0.165	1	0.684	0.697	0.122	3.984
	Radiation damage	0.254	0.403	0.399	1	0.528	1.290	0.586	2.839
	Beta0	-2.282	1.096	4.330	1	0.037	0.102