Table 1 Demographic characteristics of the study participants in the training and validation datasets.

From: A comprehensive risk score for effective risk stratification and screening of nasopharyngeal carcinoma

Variable

Training dataset

Validation dataset

Cases (%)

Controls (%)

P valuea

Cases (%)

Controls (%)

P valuea

Age

  Mean (SD)

48.38 (11.07)

49.22 (10.64)

2.15E−01

49.30 (10.83)

50.98 (10.91)

1.07E−02

  < 28

16 (3.44)

13 (2.21)

4.23E−01

7 (1.64)

10 (1.33)

1.06E−02

  28–59

377 (81.08)

477 (80.98)

 

347 (81.26)

556 (74.03)

 

  > 59

72 (15.48)

99 (16.81)

 

73 (17.10)

185 (24.63)

 

Sex

  Men

349 (75.05)

453 (76.91)

5.29E−01

330 (77.28)

581 (77.36)

1.00E+00

  Women

116 (24.95)

136 (23.09)

 

97 (22.72)

170 (22.64)

 

Smoking

  Never

174 (37.42)

217 (36.84)

7.59E−01

182 (42.62)

335 (44.61)

3.79E−01

  Formerb

34 (7.31)

37 (6.28)

 

27 (6.32)

34 (4.53)

 

  Current

257 (55.27)

335 (56.88)

 

218 (51.05)

382 (50.87)

 

Salted fish

  Yearly or less

314 (67.53)

381 (64.69)

5.84E−02

373 (87.35)

612 (81.49)

1.62E−02

  Monthly

102 (21.94)

162 (27.50)

 

48 (11.24)

113 (15.05)

 

  weekly or more

49 (10.54)

46 (7.81)

 

6 (1.41)

26 (3.46)

 

Education

  Illiterate or primary school

183 (39.35)

205 (34.80)

2.55E−01

183 (42.86)

284 (37.82)

2.22E−01

  Middle school

192 (41.29)

244 (41.43)

 

156 (36.53)

292 (38.88)

 

  High school

70 (15.05)

113 (19.19)

 

73 (17.10)

134 (17.84)

 

  College or higher

20 (4.30)

27 (4.58)

 

15 (3.51)

41 (5.46)

 

Family history

  No

406 (87.31)

568 (96.43)

5.46E−08

389 (91.10)

732 (97.47)

1.97E−06

  Yes

59 (12.69)

21 (3.57)

 

38 (8.90)

19 (2.53)

 
  1. a The P value was calculated using a two-sided t-test. Other P values for categorical variables were calculated using χ2 tests.
  2. b Individuals who had quit smoking more than 1 year before the interview were defined as former smokers.