Establishing an external quality assessment scheme for point-of-care international normalized ratio in Thailand.

Abstract

Effective warfarin therapy management has gained national interest, resulting in the increased use of point-of-care testing (POCT) for international normalized ratio (INR). External quality assessment (EQA) is recommended to ensure quality of the testing. CoaguChek XS and CoaguChek XS Plus are the only commonly available POCT INR monitors in Thailand. Therefore, Thailand NEQAS for Blood Coagulation initiated the scheme for POCT INR in 2013, including only hospitals using these devices. Questionnaires were sent to the hospitals, enquiring about their interest in EQA participation. Two surveys were distributed; each included five certified European Concerted Action on Anticoagulation (ECAA) INR plasma sets. Unsatisfactory performance was indicated by a 15% deviation from the certified mean INR value. There were 156 hospitals using the devices. Thirty-five hospitals responded to the questionnaires. Medical personnel undertaking POCT INR were limited to laboratory staff in 29 (83%) of these centers, and 31 hospitals actually participated. The medians of results from participants were the same or nearly the same as the certified mean INRs. External quality assessment for POCT INR in Thailand is feasible using the ECAA plasmas as control materials. The results therefore appear encouraging to other developing countries to establish their own EQA schemes.