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Research Articles





Dr. Sharmila Dudani

ABSTRACT: Introduction :  Pre-analytical errors account for 49% to 68% of  the errors in  medical Laboratories, which can  have a significant impact  in patient care. Material and Methods: A retrospective analysis was performed on non conformance (NC) data over a 6 month period in  a medium sized private Pathology Laboratory . The Laboratory performed all routine tests in the departments of Biochemistry, Hematology, Clinical Pathology, Serology, Cytology and Immunology. All specialized tests were outsourced to a sister concern in the same city. Non conformances were identified by feedback from Referring doctors and patients as well as documented data maintained by the laboratory. Results:  Data included 11,160 patients during the study period.  There were 3644 incidences (32.65% ) of NCs.  Sample collection reported 1928 (52.9%) incidents of which 1302 were from indoor patients and 626 from outpatient departments. 1716 (47%) incidents   were reported from billing / data entry. The most frequent NCs in collection were insufficient sample, less than 2 appropriate identifiers, and sample mislabeling, incomplete data on request forms, hemolysed sample, and wrong vial.  In data entry, incorrect / mismatched patient details, incorrect test billing and incorrect Dr Details were commonly found. Causes of recollection were hemolysed sample, insufficient sample and rejection by referral labs.  Corrective action was taken to improve non conformances. Conclusion: Importance of pre-analytical phase in overall laboratory performance cannot be overemphasized. Monitoring NCs in laboratory is essential to determine areas where further improvements are required. It is a tool of measurement of internal quality assurance as a part of continuous quality improvement.

KEY WORDS: Preanalytical : non conformance; clinical laboratory; internal quality assurance.


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