Application of Westgard internal quality control frequency on-line calculator in general chemistry internal quality control / 中华检验医学杂志

ABSTRACT

Objective:An on-line calculator for calculating the frequency of internal quality control is recommended to select quality control procedures and appropriate run lengths for general chemistry in Beijing Tongren Hospital.Methods:The cumulative controlled coefficient of variations of 10 general chemical tests in the laboratory department of Beijing Tongren Hospital for 19 consecutive months were used as the imprecision. The mean value of absolute percentage difference between the quality control results and the target value of 15 batches of 10 tests in the external quality assessment (EQA) general chemistry in 2018 was used to estimate the Bias of each test. Use the allowable range of EQA target value of the National Center for Clinical Laboratories in 2018 to estimate the total allowable error (TEa) of each test. The data were input into the Westgard internal quality control frequency calculator, and 10 different candidate statistical quality control (SQC) procedures and corresponding run lengths were calculated online, including single rule and multiple rule, number of quality control concentration levels (or test projects) ranging from 1 to 4. The SQC program with relatively simple quality control rules and long run length was selected according to the actual situation of the laboratory.Results:The 1 3s, N=3 or 1 3s, N=2 rule could be adopted for ALP and CR, and the corresponding run length was 1000. TBIL and ALT projects can adopt 1 3s, N=3 or 1 3s, N=2 rule and its corresponding run length; UA can use multiple rules 1 3S/2 2S/R 4s/4 1s, N=4 (run length 395) or 1 3S/(2of3) 2S/R 4s/3 1s N=3 (run length 259); CHO, AST and AMY can adopt two multiple rules 1 3S/2 2S/R 4s/4 1s, N=4 or 1 3S/(2of3) 2S/R 4s/3 1s, N=3 and their corresponding run length. GGT project can adopt 1 3S/2 2S/R 4s/4 1S, N=4 rule (run length 50); The run length of 10 candidate quality control rules calculated by LDH was too short, the detection performance should be improved preferentially, and the quality control rules and corresponding run length were not recommended for the time being. Conclusion:The Westgard internal quality control frequency online calculator is easy to operate. Clinical laboratories can use this calculator to select SQC program and appropriate run length. It is recommended that laboratories adjust SQC program according to the current actual situation.