2.6. Statistical analysis

SPSS22.0 statistical software package was used for statistical analysis. Count data were compared by χ² test. The measurement data were expressed by mean ± standard deviation (χ ± s). The t test was used between the 2 groups, and the difference between P < .05 was statistically significant. The PLS (Partial least squares) model was established by using SIMCA-p12.0 software. The number of damaged vessels, the number of vulnerable plaques, the thickness of the fiber cap, the maximum area of lipid core (%), the number of macrophages were set as the dependent variable y, and the other indexes (hs-CRP, miR-21, sex, age, diabetes and so on) were set as independent variables. The model R2Y (cum) 0.773 and Q2Y (cum) are 0.726, indicating that the model has a good degree of interpretation and the degree of distinction (R2 and Q2 refer to the model interpretation rate and prediction accuracy, when the cumulative amount of both is close to 1, it means that the model is ideal, with good release rate and prediction rate).