Positive Predictive Value of ICD-9 Code for Herpes Zoster Among Children During the Varicella Vaccine Era.

We examined the positive predictive value of the herpes zoster ICD-9 diagnosis code 053 in the Kaiser Permanente Northwest integrated health plan. Among children 0-17 years old, the positive predictive value was 87.1% (95% confidence interval: 84.2-89.6) and 96.8% (95% confidence interval: 95.0-98.1) during the years 1997-2002 and 2005-2009, respectively, using chart review of the medical record as the diagnostic standard.