Abstract: Objective:To analyze the time stability of ELISA internal quality control products in blood stations under cold storage conditions and establish a stability evaluation method.Method:Commercial ELISA quality control samples stored in refrigerator for 7 groups in 0,5,10,15,20,25 and 30 days were obtained.All quality control samples transferred to refrigerator were tested together with routine blood donor samples.Four items(HBsAg,anti-HCV,HIV-Ag/Ab,anti-TP)were screened in the laboratory and two kinds of commercial reagents were used in each item.As the minimum detection limit of each reagent was different and the corresponding quality control products were also different(a total of 6 kinds),a total of 8 kinds of reagents were used to test 6 kinds of quality control products in the laboratory within one day,and the test results of 8 plates detected by FAME were finally obtained.One-way ANOVA and t test together with quality control chart were used to evaluate the homogeneity and stability of quality control products at different times.Result:Except that the F value of the anti-HCV control(control lot number:201601001)was slightly higher than the critical value of F_0.05(6,14)(F=3.93,0.01＜P＜0.05),the F values of the other controls were all around 1,P values were all greater than 0.05,and there was no statistical difference.When t test α=0.01,the quality control products stored in the laboratory during the 30 days of cold storage showed overall stability.Only the anti-TP quality control products(control lot number:201611033)showed significant statistical differences on the 10th day,and showed normal performance on the 15th,20th,25th and 30th days.However,when t test α=0.05,some quality control results showed statistical differences,which were concentrated in the quality control products after 10 days of cold storage.Combining with the quality control chart,it was found that the anti-HCV quality control products(quality control product lot number:201601001)and anti-HIV quality control products(quality control product lot number:201611033)might have an attenuation trend,and the quality control chart framework itself might have offset.Conclusion:The ELISA third-party weak positive quality control products in the central laboratory can basically ensure homogeneity and stability within 30 days after being refrigerated at 2-8 ℃.A few quality control products may have an attenuation trend,which requires further observation.If necessary,the quality control products should be replaced in time and the time limit for the refrigerated storage of the quality control products should be shortened.It is necessary for the laboratory to establish its own evaluation method for the stability of quality control products to supplement the monitoring function of routine quality control charts.