PROFICIENCY TESTING
Proficiency testing (PT) is a type of external quality control to measure a laboratory's accuracy. Its purpose is to verify that the performance of each test site is in line with other labs performing the same analysis. Several times a year, 'blind' samples are sent to participants who analyze them and return the results to the PT provider. These results are then compared to other laboratories using the same testing method and a 'report card' is issued to the laboratory.