Measurement Uncertainty for Total Cholesterol, HDL-cholesterol, Triglycerides, Calculated LDL-cholesterol and non-HDL-cholesterol

Öz

Measurement uncertainty is a quantitative indicator of the quality of a result, indicates that the measurement results are performed at the level of reliability. It was aimed to calculate the measurement uncertainty for total cholesterol, HDL-cholesterol, triglycerides, calculated LDL-cholesterol, and non-HDL-cholesterol, which are frequently ordered tests in our laboratory, and to compare these values with CLIA 2019 allowable total error (TEa%) values. Our study was performed in the Central Laboratory of Karacabey State Hospital. The measurement uncertainty was determined with the calculation model defined in the Nordtest guide consisting of 6 steps. Internal and external quality control data were recorded from March to August 2020. The measurement uncertainty was calculated as 7% for total cholesterol, HDL-cholesterol and triglycerides, 12% for LDL-cholesterol and 10% for non-HDL-cholesterol. Measurement uncertainty for total cholesterol, HDL-cholesterol and triglycerides was found below the targeted TEa%. Measurement uncertainty estimation and its periodical verification aim to produce accurate results within the laboratory and provide users with an objective tool to interpret the results.

Anahtar Kelimeler

• allowable total error
• analytical phase
• measurement uncertainty
• medical laboratory
• quality control

Total Kolesterol, HDL-kolesterol, Trigliserid, Hesaplanmış LDL-kolesterol ve HDL dışı-kolesterol için Ölçüm Belirsizliği

Öz

Ölçüm belirsizliği, bir sonucun kalitesinin kantitatif bir göstergesi olup, ölçüm sonuçlarının güvenilirlik düzeyinde gerçekleştirildiğini gösterir. Çalışmamızda laboratuvarımızda sık istenen testlerden olan total kolesterol (TK), HDL-kolesterol (HDL-K), trigliserid (Tg), hesaplanmış LDL-kolesterol (LDL-K) ve HDL dışı-kolesterol (HDL dışı-K) için ölçüm belirsizliğini hesaplamak ve bu değerleri CLIA 2019 toplam izin verilen hata (%TEa) değerleriyle karşılaştırmak amaçlandı. Çalışmamız Karacabey Devlet Hastanesi Merkez Laboratuvarı’nda gerçekleştirildi. Nordtest kılavuzunda tanımlanan ve 6 adımdan oluşan hesaplama modeli ile ölçüm belirsizliği belirlendi. Mart-Ağustos 2020 dönemine ait iç ve dış kalite kontrol verileri kullanıldı. Ölçüm belirsizliği, TK, HDL-K ve Tg için %7, LDL-K için %12, HDL dışı-K için %10 olarak hesaplandı. TK, HDL-K ve Tg testleri için hesaplanan ölçüm belirsizliği, hedef %TEa değerinin altındadır. Ölçüm belirsizliğinin belirlenmesi ve düzenli olarak izlenmesi, laboratuvar içinde doğru sonuçlar üretmeyi ve kullanıcılara sonuçları yorumlamak için objektif bir araç sağlamayı amaçlar.

Anahtar Kelimeler

• toplam izin verilen hata
• analitik faz
• ölçüm belirsizliği
• medikal laboratuvar
• kalite kontrol

Kaynakça

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