Izvedba verifikacije merilnih postopkov v medicinskem laboratoriju na hematološkem analizatorju

Goručan, Jana (author), Skitek, Milan (mentor)

Mednarodni akreditacijski standard za medicinske laboratorije SIST EN ISO 15189:2012 – Medicinski laboratoriji – Zahteve za kakovost in kompetentnost zahteva, da so analizni postopki, instrumenti in reagenčni paketi, ki so uporabljeni v laboratorijih, validirani in verificirani. Validacijo in vitro diagnostike (IVD Medical Device Directive 98/79/EC) izvede proizvajalec, medtem ko smo z verifikacijo pred začetkom vpeljave analiznega postopka in analizatorja v rutinsko delo dolžni izvesti uporabniki. Z verifikacijskimi postopki želimo overiti in potrditi, da lahko značilnosti, prikazane med validacijo, uspešno ponovimo tudi v praktični klinični situaciji. Namen naloge je prikazati primere verifikacijskih postopkov (ocena merilne natančnosti in pravilnosti) na hematološkem analizatorju Advia 120, izvedenih v diagnostičnem laboratoriju Zdravstvenega doma Šentjur. Verifikacijske postopke smo izvedli po priporočilih CLSI standarda. Oceno merilne natančnosti smo izvedli z rezultati hemograma IQC proizvajalca za naslednje parametre: levkocite, eritrocite, hemoglobin, hematokrit, MCV, MCH, MCHC, MPV in trombocite. Pri oceni merilne pravilnosti smo uporabili rezultate SNEQAS v letih 2018, 2019 in 2020 za naslednje parametre hemograma: levkocite, eritrocite, hemoglobin, hematokrit, MCV in trombocite. Pridobljene rezultate smo vnesli v statistične preglednice, ki so dostopne na spletni strani organizacije The Association for Clinical Biochemistry and Laboratory Medicine – Measurement Verification. Rezultati ocene merilne natančnosti kažejo na dobro ponovljivost znotraj serije pri levkocitih, eritrocitih, hemoglobinu, hematokritu, MCV, MCH, MPV in trombocitih. Slabšo ponovljivost znotraj serije smo zaznali predvsem v visoki kontroli pri levkocitih, eritrocitih, hemoglobinu, hematokritu in MCHC. Pri oceni merilne natančnosti med serijami ne zaznavamo odstopanj v primerjavi standardnih odklonov med našimi rezultati in podanimi podatki proizvajalca pri prav vseh parametrih hemograma: levkocitih, eritrocitih, hemoglobinu, hematokritu, MCV, MCH, MCHC, MPV in trombocitih. Pri oceni merilne pravilnosti ugotavljamo, da imamo odstopanje med rezultati EQA in srednjo vrednostjo skupine, ki ni različno od nič, samo pri trombocitih, medtem ko imamo odstopanje pri levkocitih, eritrocitih, hemoglobinu, hematokritu in MCV. Rezultati EQA in srednja vrednost skupine se ne razlikuje pri levkocitih in trombocitih, medtem ko se razlikuje pri eritrocitih, hemoglobinu, hematokritu in MCV.

• Language: Slovenian
• Keywords: Hematološki analizator, validacija, verifikacija, merilna natančnost, nenatančnost, merilna pravilnost, odstopanje
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2022
• PID: 20.500.12556/RUL-141542
• Publication date in RUL: 01.10.2022

Secondary language

• Language: English
• Title: Performance verification measurement procedures in medical laboratory on hematology analyzer

Abstract

International accreditation standard for medical laboratories SIST EN ISO 15189: 2012 – Medical laboratories – Requirements for quality and competence requires that the analytical procedures, instruments and reagent packages used in the laboratories are validated and verified. The validation of in vitro diagnostics (IVD Medical Device Directive 98/79 / EC) is carried out by the manufacturer, while we are obliged to perform the verification process before the start of the analytical procedure and the routine work. By verification procedures, we want to certify that the characteristics shown during the validation can be successfully repeated in a practical clinical situation. The purpose of this work is to present examples of verification procedures on the Advia 120 hematological apparatus carried out in the diagnostic laboratory of the Health Center Šentjur. We carried out the verification procedures according to the recommendations of the CLSI standard (Clinical and Laboratory Standards Institute). The assessment of measurement accuracy was performed using the manufacturer's IQC hemogram results for the following parameters: leukocytes, erythrocytes, hemoglobin, hematocrit, MCV, MCH, MCHC, MPV and platelets. In the assessment of measurement accuracy, we used results of Slovenian National External Quality Assessment Scheme (SNEQAS) from year 2018, 2019 and 2020 for the following hemogram parameters: leukocytes, erythrocytes, hemoglobin, hematocrit, MCV and platelets. We entered the obtained results into statistical tables, which are available on the website of The Association for Clinical Biochemistry and Laboratory Medicine - Measurement Verification. The results of the measurement precision assessment show good within-run reproducibility for leukocytes, erythrocytes, hemoglobin, hematocrit, MCV, MCH, MPV and platelets. Worse reproducibility within the series was detected mainly in the high control of leukocytes, erythrocytes, hemoglobin, hematocrit and MCHC. When evaluating the measurement accuracy between batches, we do not detect deviations in the comparison of standard deviations between our results and the manufacturer's data for all hemogram parameters: leukocytes, erythrocytes, hemoglobin, hematocrit, MCV, MCH, MCHC, MPV and platelets. When evaluating the measurement accuracy, we note that we have a deviation between the EQA results and the mean value of the group, which is not different from zero, we only have platelets, while we have a deviation for leukocytes, erythrocytes, hemoglobin, hematocrit and MCV. EQA scores and group mean does not differ for leukocytes and platelets, while it does for erythrocytes, hemoglobin, hematocrit and MCV.

• Keywords: Hematology analyzer, validation, verification, measurement precision, imprecision, measurement trueness, bias