Concept: Hepatitis C Virus (HCV) - Method of Identification

Introduction

This concept provides an overview of the Hepatitis C Virus (HCV) and describes the method used at MCHP to investigate HCV in the administrative data held in the Manitoba Population Research Data Repository. The method includes the algorithm for identifying HCV in the Cadham Provincial Laboratory (CPL) - Laboratory Information Management System (LIMS) data. The method was developed to investigate the prevalence of HCV in the population for the MCHP Deliverable, The 2019 RHA Indicators Atlas by Fransoo et al (2019). A link to the online research findings is also provided.

Data Source

The data source used to identify records with a positive HCV laboratory test result in the Manitoba population from August 31, 2009 to December 31, 2017 is the Cadham Provincial Laboratory - Laboratory Information Management System (LIMS).

Method

The method for determining a positive HCV laboratory test in the RESULTS file of the CPL - LIMS data was established in partnership with the CPL. This involved analyzing the values from two variables in the RESULTS file: ANALYSIS and FORMATTED_ENTRY. The following algorithm was applied to identify positive HCV test results:

Specific Inclusion Criteria:

if analysis = 'HEPC_VL' then hcv_positive = '1';
if analysis = 'HEPC_GT' and formatted_entry ^in: ( 'Not Tested' ) then hcv_positive = '1';
if analysis = 'HEPC_HCCAG_OVRL' and formatted_entry = 'Positive' then hcv_positive = '1';
if analysis = 'HEPC_HCVAB_OVRL' and formatted_entry = 'Positive' then hcv_positive = '1';
if analysis = 'HEPC_NA' and formatted_entry = 'Positive' then hcv_positive = '1';

Exclusions:

- keep only those records that were reported to Manitoba Health (e.g. records with an invalid scrambled PHIN are removed) to reduce duplicate tests and remove 'child' tests.

For more information, please see the Hepatitis C Virus (HCV) definition in the online Indicator Definitions and Drug Codes document for this research.

Research Findings

In the Deliverable by Fransoo et al. (2019) they investigated the point prevalence of HCV in the population. For more information on the HCV prevalence findings from this research, please see section 4.11 Hepatitis C Virus (HCV) Prevalence in the online deliverable.