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Asian Institute of Research, Journal Publication, Journal Academics, Education Journal, Asian Institute
Asian Institute of Research, Journal Publication, Journal Academics, Education Journal, Asian Institute

Journal of Health and Medical Sciences

ISSN 2622-7258

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open access

Published: 04 January 2020

Quality Assurance in Medical Laboratories in Developing Countries: Assessment of Pre-Analytical Errors in a Chemical Pathology Laboratory in a Tertiary Hospital in Nigeria

Allison Frederick Igila, Ojule Aaron C.

University of Port-Harcourt, Nigeria

journal of social and political sciences
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Pages: 1-11

Keywords: Pre-Analytical Phase, Quality Assurance, Quality Indicators (QIs), Total Testing Process, International Organization for Standardization (ISO), Defect Per Million (DPM)


BACKGROUND: The total testing process is made up of the pre-analytical, analytical and post analytical phases. Most of the non-conformities to laid down laboratory procedures are known to be at the pre-analytical phase, amounting to about 70% of errors in the total testing phase. Most laboratories, in instituting total quality assurance, concentrate mainly on the analytical phase and the post analytical phase. The ISO, in a bid to correcting this oversight introduced a modifiable quality indicator system which monitors laid down processes and procedures of the laboratories. AIM- This study was therefore designed to assess the pre-analytical phase of the testing process in a Chemical Pathology laboratory of a teaching hospital in southern Nigeria. METHODS- The ISO quality indicators were modified to suit the standard operations of the Preanalytical phase of the said laboratory. With the help of a questionnaire, non-conformities to these laid- down procedures were assessed. Defects per million (DPM) of each indicator were calculated and a sigma value assigned as the performance level. A sigma value below 3 was seen as unacceptable performance and that between 3 and 4 was seen as acceptable performance. Lastly a sigma value above 4 indicated good performance. RESULT- A total of 17 quality indicators were used to assess the pre-analytical phase and 12 (70.6%) had unacceptable performance levels while 2 (11.8%) had acceptable performance levels. Only 3(17.6%) of these indicators had good performance levels. CONCLUSION- A holistic look at the performance of the quality indicators of the pre-analytical phase in this study showed that about 71% of the pre-analytical quality indicators assessed had unacceptable performance levels; 12% had acceptable performance level and only 18% had good performance level. This grossly indicates very poor quality pre-analytical sample acquisition and processing procedures. Steps therefore need to be taken to rectify these errors.


  1. Barth, J.H. (2011) ‘Clinical Quality Indicators in Laboratory Medicine: a survey of current practice in the UK’. Annals of Clinical Biochemistry, 48(3), 238-240.
  2. Da Rin, G.(2009), ‘Pre-analytical workstations: A tool for reducing laboratory errors’. Clinica Chimica Acta 404(1), 68-74.
  3. Eijsden, M.V., Van der wal, M.F., Hornstra, G. & Bonsel, G.J. (2005) ‘Can whole blood samples bestored over 24 hours without compromising stability of C-reactive protein, Retinol, Ferritin, Folic acid and Fatty acids in Epidemiologic Research?’ Clinical chemistry, 51(1), 230-232.
  4. Englezopoulou, A., Kechagia, M., Chatzikiriakou, R., Kanellopoulou, M., Valenti, M. & Masedu, F. (2016) ‘Pre Analytical Errors as Quality Indicators in Clinical Laboratory’. Austin Journal of Public Health Epidemiology, 3(5): 1048. ISSN: 2381-9014.
  5. Fraser, C.G. & Fogarty, Y.(1989) ‘Interpreting laboratory results’. British Medical Journal, 298(6689),1659-1660.
  6. Giménez-Marín, A., Rivas-Ruiz, F., Del Mar Pérez-Hidalgo, M.D.M.& Molina-Mendoza, P.(2014) ‘Pre-analytical errors management in the clinical laboratory: a five-year study’. Biochemia Medica, 24(2), 248-257.
  7. Kalra, J. & Kopargaonkar, A. (2016), ‘Quality Improvement in Clinical Laboratories: A Six Sigma Concept’. Pathology and Laboratory Medicine international, 1(1),11-20.
  8. Lima-Oliveira, G., Guidi, G.C., Guimaraes, A.V.P., Correa, J.A. & Lippi, G. (2017), ‘Preanalytical nonconformity management regarding primary tube mixing in Brazil’. Journal of Medical Biochemistry, 36(1), 39-43.
  9. Martins, J.M., Rateke, E.C.M.& Martinello, F.(2018), ‘Assessment of the pre-analytical phase of a clinical analyses laboratory’. Jornal Brasileiro de Patologia e Medicina Laboratorial, 54(4), 232-240
  10. Plebani, M., Chiozza, M.L. & Sciacovelli, L.(2013) ‘Towards harmonization of quality indicators in laboratory medicine’. Clinical Chemistry and Laboratory Medicine, 51(1), 187-195.
  11. Plebani, M., Sciacovelli, L., Aita, A. & Chiozza, M.L. (2014), ‘Harmonization of pre analytical quality indicators’. Biochemia Medica, 24(1), 105-113 
  12. Salinas, M., López-Garrigós, M., Yago, M., Ortuño, M., Carratala, A. & Aguado, C. et al. (2011) ‘Quality assessment for pre-analytical phase in clinical laboratory: a multicentric study’. Revista de Calidad Asistencial, 26(4): 264-268.
  13. Simundic, A.M., Cornes. M., Grankvist. K., Lippi, G. & Nybo, M (2014) ‘Standardization of collection requirements for fasting samples: for the Working Group on Preanalytical Phase (WG-PA) of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)’. Clinica Chimica Acta ,15(432),33-37.
  14. Singh H, Meyer AN, Thomas EJ. (2014), ‘The frequency of diagnostic errors in outpatient care: estimations from three large observational studies involving US adult populations’. BMJ Quality &Safty, 23 (9), 727-731.
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