Table 5 Comparison of subject demographics between the two groups

Sample size, n (%)

153 (100%)

108 (70.6)

45 (29.4)

NA

NA

Age (year),

mean ± SD

51.7 ± 17.4

53.3 ± 17.2

47.9 ± 17.6

1.75

0.08

Gender, n (%)

 Women

59 (38.6)

42 (38.9)

17 (37.8)

0.02

0.9

 Men

94 (61.4)

66 (61.1)

28 (62.2)

Diabetes mellitus, n (%)

 Yes

19 (12.4)

14 (13.0)

5 (11.1)

0.1

0.75

 No

134 (87.6)

94 (87.0)

40 (88.9)

WBC > 10.0 × 10⁹/L, n (%)

 Yes

131 (85.6)

91 (84.3)

40 (88.9)

0.55

0.46

 No

22 (14.4)

17 (15.7)

5 (11.1)

Tracheotomy received before surgery, n (%)

 Yes

11 (7.2)

9 (8.3)

2 (4.4)

0.26^a

0.61

 No

142 (92.8)

99 (91.7)

43 (95.6)

“Red flag” signs, n (%)

 Yes

61 (39.9)

46 (42.6)

15 (33.3)

1.14

0.29

 No

92 (60.1)

62 (57.4)

30 (66.7)

Involved deep spaces ≥ 2, n (%)

 Yes

57 (37.3)

41 (38.0)

16 (35.6)

0.08

0.78

 No

96 (62.7)

67 (62.0)

29 (64.4)

Pearson χ2 test, continuity χ2 test, and Student-t test were used for analysis

“Red flag” signs: either dyspnea, the elevated floor of mouth, or dysphagia presented

NA not applicable, SD standard deviation, WBC white blood cell count

^aContinuity χ2 test