Specimen adequacy
The rates of obtaining adequate specimens were 167 of 195 nodes (85.64%) and 169 of 195 nodes (86.67%) for S+ and S- methods, respectively. The difference in specimen adequacy (S- minus S+) between the two methods was 1.03% (95% CI, -5.83% to 7.88%). The lower bound 95% CI of the difference in specimen adequacy (-5.83%) was greater than the predetermined non-inferiority margin of -10%, demonstrating the non-inferiority of the S- method to the S+ method.Analysis of each subgroup showed that the differences in specimen adequacy were not significantly different between the two methods (Subgroup analysis of specimen adequacy obtained with and without stylet.