More than 75 laboratories around the world have been awarded this certification, for which errors in test results must be minimal, with less than four errors in a million occurrences.
Founded in 1900, the Cho Ray Hospital has 35 clinical, 11 subclinical and 8 functional departments.
It organises practice and postgraduate training for more than 2,500 medical students and 600 doctors each year.
The hospital has 1,200 beds, employs 2,270 health workers including 500 medical doctors and pharmacists, and provides treatment for about 457,000 outpatients and 67,000 inpatients per year.
Previously, the hospital also got the certificate in 2017 and 2019.