ANALISIS PRESISI DAN AKURASI HASIL KONTROL KUALITAS PADA PARAMETER PEMERIKSAAN TROMBOSIT DI UPT LABORATORIUM KESEHATAN DAERAH KABUPATEN KETAPANG

Thrombocytopenia is a key parameter for diagnosing the critical phase of Dengue Hemorrhagic Fever (DHF). As a public health laboratory in Ketapang Regency, UPT Labkesda plays a vital role in hematology testing and is responsible for ensuring examination quality through Internal Quality Control (IQC) in accordance with CLSI, ISO 15189, and the Regulation of the Minister of Health of the Republic of Indonesia (Permenkes RI) No. 81 of 2019. This study aims to evaluate the quality performance of platelet testing at UPT Labkesda Ketapang through precision and accuracy analysis. This research employed a retrospective descriptive observational design, utilizing secondary data retrieved from the logbook of the Sysmex XP-100 Hematology Analyzer for the period of January – December 2025. The data were statistically analyzed to determine the CV% and Bias%, and then visualized using Levey-Jennings charts. Two approaches Manufacturer Standard Deviation (SD) and Population Standard Deviation (SD) were compared based on Westgard rules to detect errors. The results demonstrated good precision (CV% < 5%) in 11 out of 12 months across all three control levels, and the accuracy met the Total Allowable Error criteria (TEa < 25%), despite the presence of shifts and outliers in December. The Levey-Jennings chart utilizing Population SD was more sensitive, detecting 7 to 8 errors that went unnoticed by the Manufacturer SD. In conclusion, the overall instrument performance complies with quality control standards. It is recommended that the laboratory utilize Population SD and establish stricter internal limits (CV% ≤ 3% and Bias% ≤ 7%) to enhance the early detection of analytical errors.