Reliability of administrative data to identify sexually transmitted infections for population health: a systematic review

Introduction

International Classification of Diseases (ICD) codes in administrative health data are used to identify cases of disease, including sexually transmitted infections (STIs), for population health research. The purpose of this review is to examine the extant literature on the reliability of ICD codes to correctly identify STIs.

Methods

We conducted a systematic review of empirical articles in which ICD codes were validated with respect to their ability to identify cases of chlamydia, gonorrhoea, syphilis or pelvic inflammatory disease (PID). Articles that included sensitivity, specificity and positive predictive value of ICD codes were the target. In addition to keyword searches in PubMed and Scopus databases, we further examined bibliographies of articles selected for full review to maximise yield.

Results

From a total of 1779 articles identified, only two studies measured the reliability of ICD codes to identify cases of STIs. Both articles targeted PID, a serious complication of chlamydia and gonorrhoea. Neither article directly assessed the validity of ICD codes to identify cases of chlamydia, gonorrhoea or syphilis independent of PID. Using ICD codes alone, the positive predictive value for PID was mixed (range: 18%–79%).

Discussion and conclusion

While existing studies have used ICD codes to identify STI cases, their reliability is unclear. Further, available evidence from studies of PID suggests potentially large variation in the accuracy of ICD codes indicating the need for primary studies to evaluate ICD codes for use in STI-related public health research.

Validity of ICD-10-CM Codes Used to Identify Patients with Chronic Hepatitis B and C Virus Infection in Administrative Claims Data from the Taiwan National Health Insurance Outpatient Claims Dataset

PURPOSE

To validate the use of International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes to identify patients with chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in the Taiwan National Health Insurance (NHI) Outpatient Claims Dataset.

METHODS

We conducted a retrospective study using results of HBV surface antigen (HBsAg), HBV e antigen (HBeAg), and anti-HCV antibody tests in the NHI Lab & Exam Dataset from January 1 to March 31, 2018, as the reference standard to confirm HBV and HCV infection cases. We calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) to assess the performance of HBV infection-specific ICD-10-CM codes (B180, B181, and B191) and HCV infection-specific ICD-10-CM codes (B182 and B192) recorded in the NHI Outpatient Claims Dataset to identify patients with HBV or HCV infection.

RESULTS

In total, 196,635 and 120,628 patients had analyzable results for HBsAg/HBeAg tests and anti-HCV tests, respectively. Moreover, 44,574 and 14,443 were confirmed to have HBV and HCV infection, respectively. The sensitivity, specificity, PPV, and NPV were, respectively, 46%, 83%, 45%, and 84% for HBV infection-specific ICD-10-CM codes and 47%, 99%, 81%, and 93% for HCV infection-specific ICD-10-CM codes. The sensitivity demonstrated great variation by region, clinical setting, and physician specialty.

CONCLUSION

The HBV and HCV infection-specific ICD-10-CM codes recorded by physicians in Taiwan NHI outpatient claims data in 2018 had moderate sensitivity and high specificity for both HBV and HCV infection. The PPV was high for HCV ICD-10-CM codes, yet moderate for HBV ICD-10-CM codes.