2.3. Statistical Analysis

The data were reported as percentages for categorical variables and medians and interquartile ranges for continuous variables. Annual CRs between men and women were compared using chi-squared tests. Annual CRs and the proportion of callers using ETC services were compared by age group using multiple comparisons adjusted by the Holm method.

The data were analyzed using EZR software (version 2.4-0; Saitama Medical Center, Jichi Medical University, Saitama, Japan) [13]. For all analyses, significance levels were two-tailed and p values < 0.05 were considered to indicate statistical significance.