Table 1 Demographics, behaviors, and physical condition of participants from STIs surveillance sites in Guangzhou, China, 2018 (N = 2154) ^a

Demographic characteristics

 Age (years)

   < 20

56

2.6

6

3.14

50

2.55

 < 0.001

  20–29

569

26.42

69

36.13

500

25.47

  30–39

496

23.03

75

39.27

421

21.45

  40 and above

1033

47.96

41

21.47

992

50.53

 Residence

  Guangdong

1892

87.84

173

90.58

1719

87.57

0.27

  Other provinces

262

12.16

18

9.42

244

12.43

 Marital Status

  Never married

501

23.26

63

32.98

438

22.31

0.01

  Married or Cohabitation

1600

74.28

124

64.92

1476

75.19

  Divorced or Widowed

53

2.46

4

2.09

49

2.5

 Ethnicity

  Han

2134

99.07

189

98.95

1945

99.08

1.00

  Minority

16

0.74

1

0.52

15

0.76

High-risk behaviors

 Engaged in commercial sex in the last 3 months

  Yes

789

36.63

69

36.13

720

36.68

0.94

  No

1365

63.37

122

63.87

1243

63.32

 The number of commercial partners in the last 3 months

  1

442

56.02

29

42.03

406

56.39

0.03

   > 1

285

36.12

33

47.83

248

34.44

  Missing data

73

9.25

7

10.14

66

9.17

 Engaged in casual sex in the last 3 months

  Yes

478

22.19

89

46.6

389

19.82

 < 0.001

  No

1676

77.81

102

53.4

1574

80.18

HIV-related Knowledge

 Score of HIV-related Knowledge

  Score (Mean ± SD)

6.24 ± 2.30

7.35 ± 1.50

6.13 ± 2.33

   < 6

660

30.64

19

9.95

641

32.65

 < 0.001

  6–8

1494

69.36

172

90.05

1322

67.35

 Using condoms correctly can reduce the risk to infect HIV

  Yes

1709

79.34

183

95.81

1526

77.74

 < 0.001

  No

81

3.76

2

1.05

79

4.02

  Unknown

364

16.9

6

3.14

358

18.24

 Have sex with only one partner can reduce the risk to infect HIV

  Yes

1595

74.05

168

87.96

1427

72.69

 < 0.001

  No

121

5.62

3

1.57

118

6.01

  Unknown

438

20.33

20

10.47

418

21.29

Physical condition

 Self-reported history of STIs

  Yes

199

9.24

39

20.42

160

8.15

 < 0.001

  No

1955

90.76

152

79.58

1803

91.85

Testing result in this survey

 HIV

  Yes

11

0.51

2

1.05

9

0.46

0.26

  No

2137

99.21

189

98.95

1948

99.24

  Missing data

6

0.28

0

0

6

0.31

 Syphilis

  Yes

89

4.13

13

6.81

76

3.87

0.08

  No

2059

95.59

178

93.19

1881

95.82

  Missing data

6

0.28

0

0

6

0.31

 CT

  Yes

119

5.52

14

7.33

105

5.35

0.33

  No

2008

93.22

175

91.62

1833

93.38

  Missing data

27

1.25

2

1.05

25

1.27

 NG

  Yes

90

4.18

6

3.14

84

4.28

0.57

  No

2037

94.57

183

95.81

1854

94.45

  Missing data

27

1.25

2

1.05

25

1.27