OBJECTIVETo study the method for establishing a quantization diagnostic standard for immunoglobulin A (IgA) nephropathy of qi-yin deficiency syndrome (QYDS).

METHODS1,016 patients with primary IgA nephropathy were recruited in this study. They were randomly assigned to the training sample group (344 cases of QYDS and 456 cases of non-QYDS) and the testing sample group (77 cases of QYDS and 139 cases of non-QYDS) using SPSS software. On the basis of epidemiological survey, the typing standards for QYDS and common clinical symptoms were taken as candidate correlated factors. The correlated factors were selected using binary Logistic stepwise regression. The correlated factors were scored using conditional probability conversion method. The threshold value of the quantization diagnostics was determined using maximum likelihood method. The receiver operating characteristic (ROC) curve was drawn to calculate the area under curve (AUC), sensitivity, specificity, and accuracy rating. The retrospective and prospective tests were performed on the established quantization diagnostic standard for QYDS.

RESULTSThe quantization diagnosis threshold value of IgA nephropathy of QYDS was 12 points. The sensitivity, specificity, and accuracy rating of the quantization diagnostic standard were 75.3%, 68.0%, and 71.1% in the retrospective test, as well as 60.4%, 84.4%, and 69.0% in the prospective tests. The AUC was 0.80 and 0.78 respectively.

CONCLUSIONSIt was a feasible method to set up a quantization diagnostic standard for IgA nephropathy of QYDS by taking the occurrence frequency of symptoms. But this method failed to cover the strength information of symptoms.