Data source
This study analyzed the NHIRD, which includes the healthcare data of almost 99% of Taiwanese entire population, i.e., approximately 23 million NHI beneficiaries. The database includes all insurance claims data, including outpatient visits, emergency visits, and hospitalizations. The Longitudinal Health Insurance Database(LHID), is the subset of the NHIRD comprising one million individuals randomly sampled from the 23 million NHI beneficiaries for the period from 1999 to 2013.19,20 The patients’ data were de-identified prior to release to the authors, in accordance with privacy protocols, and this research was permitted by the Institutional Review Board of Chung Shan Medical University Hospital (IRB no. CS15134).