Table 1 Predisposing and enabling characteristics of the 8808 undergraduates with low risk perception in mainland China

X1: Gender

  0=Female

5027

57.1

986

61.8

12.47

<0.001

317

58.5

4710

42.2

74.69

<0.001

  1=Male

3781

42.9

609

38.2

435

41.5

3346

57.8

X2: Sexual orientation

  0=Heterosexuals

7874

89.4

1352

84.8

28.87

<0.001

615

81.8

7259

90.1

50.28

<0.001

  1=Non-Heterosexuals

934

10.6

243

15.2

137

18.2

797

9.9

X3: Major

  0=Non-Medical

6146

69.8

1150

72.1

3.48

0.062

525

69.8

5621

69.8

0.00

0.982

  1=Medical

2662

30.2

445

27.9

227

30.2

2435

30.2

X4: Grade

  0=Freshmen

2447

27.8

506

31.7

10.33

0.001

159

21.1

2288

28.4

18.06

<0.001

  1=Non-freshmen

6361

72.2

1089

68.3

593

78.9

5768

71.6

X5: Age at first sex (Years)

  0=14 (Late)

8639

98.1

1582

99.2

9.57

0.002

682

90.7

7957

98.8

238.59

<0.001

  1=14 (Early)

169

1.9

13

0.8

70

9.3

99

1.2

X6: HIV-related knowledge (Range: 0-12)

  0=High (≥8)

5654

64.2

833

52.2

82.38

<0.001

408

54.3

5246

65.1

35.32

<0.001

  1=Low (8)

3154

35.8

762

47.8

344

45.7

2810

34.9

X7: HIV-related stigma (Range: 0-24)

  0=Low (≥18)

4144

47.0

723

45.3

1.60

0.206

245

32.6

3899

48.4

69.09

<0.001

  1=High (18)

4664

53.0

872

54.7

507

67.4

4157

51.6

X8: Testing history

  0=Never

8204

93.1

1445

90.6

13.03

<0.001

675

89.8

7529

93.5

14.72

<0.001

  1=Ever

604

6.9

150

9.4

77

10.2

527

6.5

X9: Condom use self-efficacy (Range: 0-8)

  0=Low (0-7)

5674

64.4

1249

78.3

117.01

<0.001

518

68.9

5156

64.0

7.15

0.008

  1=High (=8)

3134

35.6

346

21.7

234

31.1

2900

36.0

X10: Monthly expenditure

  0=Low (2000 Yuan)

8004

90.9

1501

94.1

17.92

<0.001

601

79.9

7403

91.9

118.89

<0.001

  1=High (≥2000 Yuan)

804

9.1

94

5.9

151

20.1

653

8.1

X11: Residential areas

  0=Rural

5890

66.9

1135

71.2

11.33

0.001

429

57.0

5461

67.8

35.81

<0.001

  1=Urban

2918

33.1

460

28.8

323

43.0

2595

32.2

X12: Knowledge of local AIDS organization

  0=No

4293

48.7

820

51.4

3.86

0.050

414

55.1

3879

48.2

13.12

<0.001

  1=Yes

4515

51.3

775

48.6

338

44.9

4177

51.8

X13: Awareness of the national AIDS policy

  0=awareness

5645

64.1

1214

76.1

86.92

<0.001

428

56.9

5217

64.8

18.39

<0.001

  1=awareness

3163

35.9

381

23.9

324

43.1

2839

35.2