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Abstract When traditional statistical quality control protocols, represented by the Westgard protocol were applied to infectious disease serology, the rejection limits were questioned because of the high rejection probability. We first define the probability of false rejection (Pfr) and error detection (Ped) for infectious disease serology. QC data in 6 months were collected and the Pfr of each rule in the Westgard protocol and Rilibak protocol was evaluated. Then, as improvements, we chose different rules for negative and positive QC data to constitute an asymmetric protocol, furthermore, while reagent lot changes, the mean value of QC protocol is reset with the first 15 QC results of new lot reagent. QC materials and Standard Reference Materials were tested synchronously in the next 6 months, to verify whether the Pfr and Ped of the asymmetric protocol could meet the requirement. Protocol 1 exhibited the higher level of rejection rate among the two protocols, especially after reagent lot changes; Pfr below the lower control limit (LCL) was 1.39–21.78 times higher than the upper control limit (UCL); false rejections were more likely to occur in negative QC data, with Pfr-total of 27–65%. The asymmetric protocol can significantly reduce the proportion of analytes with Pfr by over 20%. Systematic error due to reagent lot changes and random error due to routine QC data variation were considered potential factors for excessive Pfr. Asymmetric QC protocol that can reduce Pfr by different control limits for negative and positive QC data.

Introduction: Internal Quality Control (IQC) is run to assess the day-to-day performance of an analytical process, ensuring the reliability of patient results. However, commercial internal quality materials can be expensive and inaccessible for many laboratories. Therefore, there is a need for an effective and economical alternative to commercial IQC. Aim: To evaluate the effectiveness and stability of pooled sera as an IQC material. Materials and Methods: A laboratory study was conducted over a period of 50 days, from January 10 to February 28, 2023, in the Department of Biochemistry at Dr. Rajendra Prasad Government Medical College (DRPGMC), Kangra, Himachal Pradesh, India. Serum samples (150 μL) were collected from 100 leftover samples over a span of 10 days. The serum was thoroughly mixed and distributed into 75 aliquots. Commercial IQC was also reconstituted and distributed into 75 aliquots. Both the commercial and pooled sera IQC were stored at -20°C. One aliquot of pooled sera was analysed daily for 16 routine biochemistry parameters, along with the commercial IQC, for the entire 50-day period. The results from both materials were interpreted using L-J chart and Westgard multirule. The stability of pooled sera for these routine parameters was assessed by comparing the mean values of the biochemical parameters on day 1 and day 50. Data analysis was performed using Statistical Package for the Social Sciences (SPSS) version 20.0 software, and a paired t-test with a p-value

Shui Fu,1 Liang Zhang,1 Qi-Lei Hu,1,2 Zuo-Jie Li3 1Department of Clinical Laboratory, Linping Campus, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 311000, People’s Republic of China; 2Quality Management Section, Linping Campus, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, 311100, People’s Republic of China; 3Department of Clinical Laboratory, The People’s Hospital of Cangnan Zhejiang, Cangnan County, Zhejiang, 325800, People’s Republic of ChinaCorrespondence: Zuo-Jie Li, Department of Clinical Laboratory, The People’s Hospital of Cangnan Zhejiang, No. 2288 Yucang Road, Cangnan County, Zhejiang, 325800, People’s Republic of China, Tel +86 577-64810162, Email acdemicarticle@126.comObjective: This study establish and evaluate an internal quality control system for erythrocyte sedimentation rate (ESR) by a “relay” mode based on samples from relevant patients.Methods: The method for establishing a new internal quality control system for ESR by a “relay” mode based on patient’s samples was executed from February 2021 to July 2021. In this paper, a total of 219 outpatients were recruited for ESR determination, and their blood samples were stored at 4 °C or room temperature for 24 h. Subsequently, the samples were re-measured for ESR, and the re-measured values were compared with the initial values. The patient samples (15± 1mm/h and 50± 3mm/h) were selected after the TEST1 ESR analyzer was calibrated, and were stored overnight at 4 °C and measured again the following day. The percentage deviation was determined and entered into the quality control management module for internal quality control. Next, we analyzed the median distribution trend of the patients’ ESR values measured by our laboratory every day over five months, as well as the external quality assessment (EQA) results for ESR obtained from the National Center for Clinical Laboratories (NCCL).Results: The ESR of the room temperature samples after 24 h of storage had significantly decreased (P=0.001), while there was no noticeable difference for those stored at 4 °C (P=0.197). Results of the internal quality control in March were satisfactory, and there was no significant deviation in the median ESR relay results within five months. Besides, the EQA results for the ESR data obtained from NCCL were excellent.Conclusion: As a precise and practical new method, the ESR relay internal quality control method can be used to scientifically determine the stability and accuracy of the TEST1 ESR analyzer.Keywords: erythrocyte sedimentation rate, ESR, fully automatic ESR analyzer, quality control, fresh blood sample, Westgard rules