Evaluation of Laboratory Quality Control Through Hematology External Quality Assurance Scheme (EQAS) Performance: A Hospital-Based Study at CARI, Guwahati

ABSTRACT Background: Quality Assurance is aimed at ensuring quality test results. The purpose of quality assurance is to give relevant, reliable, timely test results which are interpreted correctly. In order to achieve the precision, accuracy and reliability of laboratory test results, accreditation and EQAS are very important procedure. An external quality control program consists in a systematic distribution of several control samples among a number of laboratories and an evaluation of results obtained by an organization external to the participant laboratory. EQAS assesses the analytical performance of a laboratory relative to its peer (laboratories using the same method or instruments) reference standards, and /or reference laboratories. When participating laboratories submits its results for EQAS sample, the EQAS program evaluates and reports the performance of the laboratory based on statistical methods. The laboratories review their EQAS reports and take action, if necessary, which helps to improve the quality of the laboratory. This study was to assess our performance as a participating laboratory in the EQAS program services and investigate the impact of corrective and preventive actions implemented, where necessary, to enhance EQAS performance. By conducting this evaluation, we aimed to gain insights into our laboratory’s proficiency in EQAS and identify areas for improvement to further enhance the quality of our services. Aim & objectives: The objectives behind this study was to Study the performance of Clinical Laboratory, CARI- Guwahati with reference to Hematology EQAS and to Study the EQAS performance of WBC, RBC, Hb, HCT, MCV, MCH, MCHC, PLT, RETIC in Hematology. Material & Methods: The study was carried out at clinical laboratory of CARI -Guwahati for a period from January 2023 to August 2025 for total of 9 EQAS Hematology parameter using 10 EQAS reports. Results & Observation: In our study, majority of the parameters achieved excellent z-score for hematology with zero outlier between January 2023 to August 2025. Mean z- score of most of pathological parameters achieved the excellent performance z- score i.e. between -1 to +1 except for Platelet count and Retic count which achieved good performance Z- score i.e. between ± 1.01 and ± 2.00. Conclusion: EQAS program plays an important role in improving the efficacy of a laboratory services, thereby optimizing the overall quality of a health care system. From January 2023 to August 2025, EQAS experience in the clinical laboratory showed satisfactory results. Clinical Laboratory will continue with the EQAS programme to ensure the quality of test reports with similar corrective and preventive action implemented during this study period. Special emphasis will also be given on platelet count and Retic count to improve z-score from good performance to excellent performance. Keywords: Quality, EQAS, Clinical Laboratory, Hematology, Z- score.