Skip to main content

Table 1 Basic Information Distribution in Case and Control Groups

From: Effect of GRM7 polymorphisms on the development of noise-induced hearing loss in Chinese Han workers: a nested case-control study

Variables

Case (n = 292)

Control (n = 584)

Statistics

p

Age, year

 20~30

45 (15.4%)

104 (17.8%)

  

 30~40

79 (27.1%)

153 (26.2%)

  

 40~50

134 (45.9%)

270 (46.2%)

  

 50~60

34 (11.6%)

57(9.8%)

1.381‡

0.710

Noise exposure duration, year

18.860 (8.500, 27.750)

18.509 (8.167, 26.917)

−0.692§

0.489

CNE, dB(A)*

97.844 (94.686, 101.522)

97.767 (94.854, 101.195)

−0.153§

0.878

HTL, dB(A) †

50.980 (44.042, 55.833)

18.293 (12.500, 24.000)

−24.153§

<0.001

Height, cm

170.366 (167.000, 174.750)

169.993 (166.000, 174.000)

−1.004§

0.315

Gender

 Male

281 (96.2%)

560 (95.9%)

  

 Female

11 (3.8%)

24 (4.1%)

0.060‡

0.807

level of environmental noise exposure, dB(A)

  ≤ 85

121 (41.4%)

254 (43.5%)

  

  > 85

171 (58.6%)

330 (56.5%)

0.336‡

0.562

Tinnitus

 Yes

196 (67.4%)

316 (54.2%)

  

 No

95 (32.6%)

267 (45.8%)

12.837‡

<0.001

Smoking

 Yes

181 (62.0%)

341 (58.4%)

  

 No

109 (38.0%)

243 (41.6%)

1.045‡

0.307

Drinking

 Yes

203 (69.5%)

399 (68.3%)

  

 No

89 (30.5%)

185 (31.7%)

0.130‡

0.718

Hypertension

 Yes

112 (38.4%)

242 (41.4%)

  

 No

180 (61.6%)

342 (58.6%)

0.768‡

0.381

  1. Evaluation of the matching effects in the case and control groups by comparing the basic information distribution between them
  2. *CNE: cumulative noise exposure
  3. †HTL: the binaural average hearing threshold level in high frequencies
  4. ‡Pearson chi-square test
  5. §Wilcoxon rank sum test