. 2017 May 18;65(1):166–174. doi: 10.1093/cid/cix244

Table 3.

Effect of Antibiotic Allergy Testing on Antibiotic Usage

Antibiotic Classification	Period of Analysis			Crude OR^a (95% CI)		Adjusted OR^b (95% CI)
	Pre-AAT		Post-AAT	3 mo Pre- vs 3 mo Post-AAT	12 mo Pre- vs 3 mo Post-AAT	3 mo Pre- vs 3 mo Post-AAT	12 mo Pre- vs 3 mo Post-AAT
	12 mo, No. (%) (n = 263)	3 mo, No. (%) (n = 155)	3 mo, No. (%) (n = 125)	3 mo Pre- vs 3 mo Post-AAT	12 mo Pre- vs 3 mo Post-AAT	3 mo Pre- vs 3 mo Post-AAT	12 mo Pre- vs 3 mo Post-AAT
NS penicillin	27 (10.3)	11 (7.1)	29 (23.2)	4.69 (2.02–10.92)	3.34 (1.69–6.63)	2.81 (1.45–5.42)	4.07 (1.78–9.32)
NS β-lactam	49 (18.6)	25 (16.1)	49 (39.2)	4.67 (2.27–9.58)	3.68 (2.05–6.60)	3.54 (1.98–6.33)	5.27 (5.22–5.31)
βL/βLI	13 (4.9)	5 (3.2)	27 (21.6)	11.17 (3.25–38.36)	6.58 (2.83–15.26)	9.25 (3.57–24.01)	25.02 (4.71–132.87)
Restricted antibiotic	150 (57)	98 (63%)	20 (16)	0.11 (.06–.20)	0.13 (.07–.24)	0.16 (.09–.29)	0.11 (.06–.22)

Abbreviations: AAT, antibiotic allergy testing; βL/βLI, β-lactam/β-lactamase inhibitor; CI, confidence interval; NS, narrow-spectrum; OR, odds ratio.

^aFrom univariable mixed-effects logistic regression models.

^bFrom multivariable mixed-effects logistic regression models, controlled for age-adjusted Charlson comorbidity index, infective episode setting (inpatient/outpatient), and indication category.