Statistical analysis
Mean ± standard deviation or median and interquartile range was used for continuous variables. Categorical variables were summarized as frequencies and percentages. Continuous variables were compared using univariate analysis, and the chi-square test or Fisher exact test were performed for categorical variables. Multivariate logistic regression analysis was performed to find independent predictors of inappropriate aspirin use. A p-value <0.05 was considered statistically significant. Statistical analysis was performed using statistical software (SPSS version 13.0, SPSS, Chicago, IL, USA).