| NHIRD | National Health Insurance Research Database; |
| aHR | adjusted hazard ratio; |
| ICD-9-CM | International Classification of Diseases, Ninth Revision, Clinical Modification |
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.