Sources of Error in Coagulation
Testingcontinued
Hematology Review 365
ERROR COMMENT
Improper storage of specimen
Improper storage or reconstitution
of reagents
Equipment malfunction, e.g., temperature,
timer, detector, volumes dispensed
Should be stored in vertical position at RT with stopper on to prevent change in pH.
Specimens for PT must be tested within 24 hr of collection, APTT within 4 hr. (If APTT is
for monitoring heparin, must be centrifuged within 1 hr of collection.)Run normal & abnormal controls every 8 hr & with each change of reagents to verify system
performance.Run normal & abnormal controls every 8 hr & with each change of reagents to verify system
performance.