4. Statistical analysis
All data was processed by SPSS 22.0 statistical software. Descriptive
research is adopted, and the measurement data in line with normal
distribution were expressed as mean ± standard deviation (x±s); the
measurement data of non-normal distribution were expressed by median;
the counting data were expressed by (n, %); Logistic regression
analysis was used in multivariate analysis. P < 0.05 indicated
statistical difference.