The Chang Gung Research Database: Multi-Institutional Real-World Data Source For Traditional Chinese Medicine In Taiwan

Background The Chang Gung Research Database (CGRD), the largest multi-institutional electronic medical records collection in Taiwan, has been used to establish real-world evidence related to traditional Chinese medicine (TCM). We aimed to evaluate patient characteristics and representativeness of TCM patients in CGRD.Methods We identified a cohort of patients who had TCM records both from CGRD and from Taiwan's National Health Insurance Database (NHIRD) during 2010-2015 to investigate the representativeness of CGRD for TCM uses. The NHIRD was considered as reference because it covers all medical claims from 99.9% of the entire Taiwanese population. We investigated the coverage rates of TCM patients within CGRD compared to NHIRD, and compared the characteristics of patients between CGRD and NHIRD including age, sex, and 15 health conditions.Results We identified 71 002 average annual patients within the CGRD, which accounted for 1.1% of the patients from the NHIRD. The patients from CGRD were older than those from NHIRD (>= 65: 16.6% vs. 9.9% for CGRD vs. NHIRD). The ratios of female over male patients were 1.7 vs. 1.5 for CGRD vs. NHIRD. We found higher patient coverage rates for patients with major comorbidities in CGRD, specifically for neoplasm (9.2%) and mental disorders (6.0%). The most frequently prescribed Chinese herbal medicines in CGRD included Jia-Wei-Xiao-Yao-San, Xiang-Sha-Liu-Jun-Zi-Tang and Gui-Lu-Er-Xian-Jiao.Conclusion Higher patient coverage rates were found in CGRD for TCM patients with major comorbidities. Investigators should note possible selection bias since TCM patient disorders may be more severe in CGRD than in the NHIRD.