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Author Spotlight: Advancements and Challenges in Hepatitis B Virus Detection
Published on: December 15, 2023
Comparative effectiveness research of chronic hepatitis B and C cohort study (CHeCS): improving data collection and
Mei Lu1, Loralee B Rupp, Anne C Moorman
1Departments of Public Health Sciences, Center for Health Services Research, and Gastroenterology, Henry Ford Health System, One Ford Place, 3E, Detroit, MI, 48202, USA, mlu1@hfhs.org.
Insights
The Chronic Hepatitis Cohort Study (CHeCS) used electronic health records and adaptive methods to efficiently identify patients with chronic hepatitis B (HBV) and C (HCV). This approach significantly improved the accuracy of cohort selection for comparative effectiveness research.
Area of Science:
- Comparative effectiveness research
- Health informatics
- Longitudinal cohort studies
Background:
- The Chronic Hepatitis Cohort Study (CHeCS) is a longitudinal observational study focused on chronic hepatitis B (HBV) and C (HCV) infections.
- Investigated risks and benefits of treatments and care in patients across four US health systems.
Purpose of the Study:
- To evaluate the effectiveness of comparative effectiveness methods for cohort selection.
- Hypothesized that centralized data management and adaptive cohort selection would improve efficiency, data quality, and reduce costs.
Main Methods:
- Utilized electronic health records (EHR) for primary data collection and chart abstraction for case confirmation.
- Employed a centralized data management system with parallel data sources (direct EHR and electronic data capture).
- An adaptive Classification and Regression Tree (CART) model was used to optimize electronic variable selection for improved case ascertainment.
Main Results:
- Collected over 16 million patient records from 2006-2008, with 99.2% data from EHR.
- Initial electronic criteria identified 12,144 patients; chart abstraction confirmed 10,098 with positive predictive values (PPV) of 79% for HBV and 83% for HCV.
- CART-optimized models significantly enhanced PPV to 88% for HBV and 95% for HCV.
Conclusions:
- CHeCS successfully leveraged electronic data and adaptive cohort identification for efficient comparative effectiveness research.
- The adaptive CART model substantially improved the positive predictive value for cohort identification, enhancing study efficiency.
Background And Aims:
The Chronic Hepatitis Cohort Study (CHeCS) is a longitudinal observational study of risks and benefits of treatments and care in patients with chronic hepatitis B (HBV) and C (HCV) infection from four US health systems. We hypothesized that comparative effectiveness methods-including a centralized data management system and an adaptive approach for cohort selection-would improve cohort selection while controlling data quality and reducing the cost.
Methods:
Cohort selection and data collection were performed primarily via the electronic health record (EHR); cases were confirmed via chart abstraction. Two parallel sources fed data to a centralized data management system: direct EHR data collection with common data elements, and chart abstraction via electronic data capture. An adaptive Classification and Regression Tree (CART) identified a set of electronic variables to improve case ascertainment accuracy.
Results:
Over 16 million patient records were collected on 23 case report forms in 2006-2008. The vast majority of data (99.2%) were collected electronically from EHR; only 0.8% was collected via chart abstraction. Initial electronic criteria identified 12,144 chronic hepatitis patients; 10,098 were confirmed via chart abstraction with positive predictive values (PPV) 79 and 83% for HBV and HCV, respectively. CART-optimized models significantly increased PPV to 88 for HBV and 95% for HCV.
Conclusions:
CHeCS is a comparative effectiveness research project that leverages electronic centralized data collection and adaptive cohort identification approaches to enhance study efficiency. The adaptive CART model significantly improved the positive predictive value of cohort identification methods.
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