External Quality Assessment for HIV Serology Testing of Laboratories in Central and Eastern Thailand 2018-2022

Abstract

External Quality Assessment is the important process for evaluate the laboratory performance due to ensure that the analysis results are accurate and reliable. Participation in proficiency testing program is the once requirement for accreditation of ISO 15189 assessment. In this study, the objective was to evaluate laboratory quality in National External Quality Assessment Scheme for HIV serology testing program in the Central and Eastern regions during the fiscal year 2018 – 2022. Participant laboratories were 143 – 194 laboratories performing HIV serology testing. Quality assessment based on compliance with assigned value. The operations consist of sample delivery to member 3 times in a year, result accumulation, result evaluation and reporting. This study found the response rate of participants were 91.70%, 93.83%, 94.31%, 94.27% and 92.72%, respectively. The percentage of accuracy results were 95.17%, 95.36%, 97.45%, 97.05% and 89.87%, respectively. The most common causes of error are incorrect records or incorrect conclusions, contamination and sample switching. The result of laboratory’s testing in repeat sample at 98.79%, 99.23%, 99.45%, 99.27% and 99.24%, respectively. In the part of final interpretation, It found the laboratories were not followed the Thailand guideline on HIV/AIDS Diagnosis, Treatment and Prevention but the trend of misinterpretation was decrease after getting the recommendation from the provider. The information from this study is useful for laboratory improvement and prevention. It also beneficial to develop a proficiency testing program to be more effective.