TURKISH JOURNAL OF BIOCHEMISTRY-TURK BIYOKIMYA DERGISI, vol.46, no.6, pp.639-645, 2021 (SCI-Expanded)
Objectives Measurement uncertainty is described as a magnitude indicates the distribution of the measurement results. AACB Guideline suggests that bias should not be included in the uncertainty calculation contrary to Nordtest Guideline. The aim of the study is to calculate the uncertainty values of certain complete blood count (CBC) parameters and evaluate the contribution of bias. Methods This retrospective study was performed with the quality control data of January-December 2017 of two different CBC autoanalyser models (Beckman Coulter LH780 and DXH800). Measurement uncertainties were calculated according to AACB and Nordtest Guidelines. Imprecision, i.e. measurement uncertainty, varies with concentration. Imprecision values of user manuals, as performance characteristics of autoanalyzers, were used for assessment. Results User manuals imprecision values of different levels of platelets are between 3.3 and 14%. As the concentrations of platelets decrease, imprecision is observed to increase. This is expected to be parallel with measurement uncertainty. Contrary to user manuals, uncertainty values of AACB found to be so close to each other (between 3.41% and 4.80%), regardless of concentration level. However Nordtest guideline is more compatible with user manuals (between 6.97% and 15.35%). Conclusions When evaluated with the performance expectations, bias should be used in measurement uncertainty. Calculation of uncertainty for different concentration level is also important. Amac olcum belirsizligi, bir buyukluk olarak olcum sonuclarinin dagilimini ifade eder. AACB Kilavuzu, Nordtest Kilavuzunun aksine, biasin belirsizlik hesaplamasina dahil edilmesini onermemektedir. calismanin amaci, belirli tam kan sayimi (CBC) parametrelerinin belirsizlik degerlerini hesaplamak ve biasin katkisini degerlendirmektir. Gerec ve Yontemler Bu retrospektif calisma, iki farkli CBC otoanalizor modelinin (Beckman Coulter LH780 ve DXH800) Ocak-Aralik 2017 kalite kontrol verileriyle gerceklestirildi. olcum belirsizlikleri AACB ve Nordtest Kilavuzlarina gore hesaplandi. Impresizyon, dolayisiyla olcum belirsizligi, konsantrasyona gore degisir. Belirsizlik sonuclarini degerlendirmede otoanalizorlerin kullanim kilavuzlarinda yer alan impresizyona dayali performans ozellikleri kullanilmistir. Bulgular Farkli trombosit duzeylerinin kullanim kilavuzlarindaki impresizyon degerleri %3.3-%14 arasindadir. Trombosit konsantrasyonu dustukce impresizyon artar. Bunun olcum belirsizligi ile paralel olmasi beklenir. Kullanim kilavuzlarinin aksine, AACB'ye gore hesaplanan belirsizlik degerleri, konsantrasyon seviyesinden bagimsiz olarak birbirine cok yakin (%3.41-%4.80 arasinda) bulundu. Bununla birlikte, Nordtest kilavuzunun sonuclari,otoanalizorlerin kullanim kilavuzlari ile daha uyumlu bulundu (%6.97-%15.35 arasinda).