Table 2.

Positive and Negative Predictive Values of International Classification of Diseases Clinical Modification 9th and 10th Edition Codes for Surveillance of Surgical Site Infections

		PPV			NPV
Procedure	ICD Range	ICD-9 (95% CI)	ICD-10 (95% CI)	Difference (95% CI)	ICD-9 (95% CI)	ICD-10 (95% CI)	Difference (95% CI)
Colectomy	Narrow	0.52 (0.47-0.57)	0.50 (0.43-0.58)	−0.02 (−0.12-0.09)	0.96 (0.95-0.96)	0.97 (0.97-0.97)	0.02 (−0.02- −0.007)
Hysterectomy	Narrow	0.46 (0.39-0.53)	0.47 (0.37-0.59)	0.02 (−0.16-0.18)	0.99 (0.99-0.99)	0.99 (0.99-1.00)	0.01 (−0.01-0.0)
All	Narrow	0.50 (0.46-0.54)	0.50 (0.44-0.55)	−0.01 (−0.09-0.08)	0.97 (0.97-0.98)	0.98 (0.98-0.98)	0.01 (−0.01-0.0)
Colectomy	Expanded	0.35 (0.32-0.38)	0.29 (0.25-0.33)	−0.06 (−0.13-0.003)	0.97 (0.96-0.97)	0.97 (0.97-0.98)	0.01 (−0.02- −0.001)
Hysterectomy	Expanded	0.36 (0.32-0.41)	0.26 (0.21-0.32)	−0.10 (−0.21-0.01)	0.99 (0.99-0.99)	1.00 (0.99-1.00)	−0.004 (−0.008-0.001)
All	Expanded	0.35 (0.33-0.38)	0.28 (0.25-0.32)	−0.07 (−0.13−-0.02)	0.98 (0.98-0.98)	0.98 (0.98-0.98)	−0.001 (−0.006-0.003)

PPV, positive predictive value; NPV, negative predictive value, CI, confidence interval. ICD, International Classification of Diseases