Comparison of the Improved Method and the Traditional Method for Toluidine Red Unheated Serum Test in Syphilis Screening / 现代检验医学杂志

ABSTRACT

Objective To compare the detection performance of the modified serum test (TRUST) method and the traditional method in syphilis screening.Methods A series of TRUST high titer syphilis serum was diluted,and the positive rate of each method was calculated by using the improved method and the traditional method.Comparison of two detection methods of C50,C5 ～ C95 interval,as well as the accuracy of the density curve,and the consistency of the two methods were compared,and diagnostic performance were compared.Results The improved method of C50 was less than the traditional method of C50,and the improved method of C5 ～ C95 range was narrower than the traditional method,compared with the traditional method.The improved method of the non precision density curve was steeper than the traditional method,and the two confidence interval of the consistency degree of the 95％ methods was 73.4％ to 95.8％.The diagnostic sensitivity (SEN),diagnostic specificity (SPE),positive predictive value (PPV),negative predictive value (NPV) and diagnostic efficiency(DF) of the improved method were 64.29 ％,99.1％,85.71％,97.05 ％ and 96.39 ％,respectively.The SEN,SPE,PPV,NPV and DF of the traditional methods were 3.75 ％,98.49 ％,75 ％,96.18 ％ and 95 ％,respectively.The improved method was superior to the traditional methods in the two aspects of SEN and PPV (x2 =8.25,10.03,all P＜0.05),with the statistically significant difference.The improved method was slightly higher than the traditional method in SPE,NPV and DF (x2 =2.39,3.45,4.03,all P＞0.05),with the no statistically significant difference.Conclusion The precision,diagnostic sensitivity and diagnostic specificity of the improved method was higher than that of the traditional method,and it can be applied to the detection of large batch samples with the aid of the full automatic enzyme immunoassay instrument.The improved method can be used to replace the traditional method for syphilis screening.