Table 1 Characteristics and sleep quality of nurses in the emergency department in public hospitals in Shandong, China

Number of subjects

4730

3349

1044

337

Age

35.3 ± 6.8

35.9 ± 6.5

34.6 ± 7.1

32.5 ± 7.4

Sex

 Male

545 (11.5%)

365 (10.9%)

132 (12.6%)

48 (14.2%)

 Female

4185 (88.5%)

2984 (89.1%)

912 (87.4%)

289 (85.8%)

Marital status

 Never married

677 (14.3%)

472 (14.1%)

153 (14.7%)

52 (15.4%)

 Married/cohabiting

3427 (72.5%)

2446 (73.0%)

748 (71.6%)

233 (69.1%)

Divorced/separated/widowed

626 (13.2%)

431 (12.9%)

143 (13.7%)

52 (15.4%)

 Never/almost never

2091 (44.2%)

1475 (44.0%)

462 (44.3%)

154 (45.7%)

 Sometimes

1088 (23.0%)

779 (23.3%)

238 (22.8%)

71 (21.1%)

 Often

886 (18.7%)

639 (19.1%)

188 (18.0%)

59 (17.5%)

 Daily/almost daily

665 (14.1%)

456 (13.6%)

156 (14.9%)

53 (15.7%)

BMI

 < 18.5

373 (7.9%)

269 (8.0%)

79 (7.6%)

25 (7.4%)

 18.5 ~ 23.9

2413 (51.0%)

1668 (49.8%)

551 (52.8%)

194 (57.6%)

 24.0 ~ 27.9

1168 (24.7%)

851 (25.4%)

249 (23.9%)

68 (20.2%)

≥ 28.0

776 (16.4%)

561 (16.8%)

165 (15.8%)

50 (14.8%)

 Never/almost never

2677 (56.6%)

1852 (55.3%)

615 (58.9%)

210 (62.3%)

 Sometimes

1194 (25.2%)

863 (25.8%)

253 (24.2%)

78 (23.1%)

 Often

859 (18.2%)

634 (18.9%)

176 (16.9%)

49 (14.5%)

  < Ұ4000

1393 (29.5%)

1026 (30.6%)

289 (27.7%)

78 (23.1%)

 Ұ4000-

1442 (30.5%)

1029 (30.7%)

313 (30.0%)

100 (29.7%)

 Ұ6000-

1259 (26.6%)

864 (25.8%)

293 (28.1%)

102 (30.3%)

 Ұ8000-

439 (9.3%)

298 (8.9%)

102 (9.8%)

39 (11.6%)

Ұ10,000-

197 (4.2%)

132 (3.9%)

47 (4.5%)

18 (5.3%)

Smoking

 Never smoked

4077 (86.2%)

2893 (86.4%)

896 (85.8%)

288 (85.5%)

 Ex-smoker

332 (7.0%)

231 (6.9%)

75 (7.2%)

26 (7.7%)

 Current smoker

321 (6.8%)

225 (6.7%)

73 (7.0%)

23 (6.8%)

Educational level

 Lower than junior college

1854 (39.2%)

1352 (40.4%)

389 (37.3%)

113 (33.5%)

 Junior college

2297 (48.6%)

1633 (48.8%)

512 (49.0%)

152 (45.1%)

 Bachelor

506 (10.7%)

329 (9.8%)

121 (11.6%)

56 (16.6%)

Master or above

73 (1.5%)

35 (1.0%)

22 (2.1%)

16 (4.7%)

  =0

441 (9.3%)

276 (8.2%)

112 (10.7%)

53 (15.7%)

  = 1

3139 (66.4%)

2194 (65.5%)

719 (68.9%)

226 (67.1%)

  = 2

1120 (23.7%)

856 (25.6%)

208 (19.9%)

56 (16.6%)

  > 2

30 (0.6%)

23 (0.7%)

5 (0.5%)

2 (0.6%)

Professional rank

 Registered

1294 (27.4%)

952 (28.4%)

276 (26.4%)

66 (19.6%)

 Primary

2450 (51.8%)

1856 (55.4%)

459 (44.0%)

135 (40.1%)

 Intermediate

720 (15.2%)

382 (11.4%)

235 (22.5%)

103 (30.6%)

 Senior/deputy senior

266 (5.6%)

159 (4.7%)

74 (7.1%)

33 (9.8%)

 Years of service

11.2 ± 6.5

12.1 ± 5.8

9.4 ± 6.7

7.1 ± 8.7

 Never

515 (10.9%)

359 (10.7%)

121 (11.6%)

35 (10.4%)

 1–3

1179 (24.9%)

856 (25.6%)

246 (23.6%)

77 (22.8%)

 4–6

1799 (38.0%)

1325 (39.6%)

365 (35.0%)

109 (32.3%)

  ≥ 7

1237 (26.2%)

809 (24.2%)

312 (29.9%)

116 (34.4%)

  < 40

1331 (28.1%)

1021 (30.5%)

249 (23.9%)

61 (18.1%)

 40–45

2157 (45.6%)

1530 (45.7%)

476 (45.6%)

151 (44.8%)

  > 45

1242 (26.3%)

798 (23.8%)

319 (30.6%)

125 (37.1%)

  < 30

996 (21.1%)

765 (22.8%)

186 (17.8%)

45 (13.4%)

 30–60

2028 (42.9%)

1405 (42.0%)

466 (44.6%)

157 (46.6%)

  > 60

1706 (36.1%)

1179 (35.2%)

392 (37.5%)

135 (40.1%)

  < 30

1325 (28.0%)

1009 (30.1%)

253 (24.2%)

63 (18.7%)

 30–60

1753 (37.1%)

1211 (36.2%)

405 (38.8%)

137 (40.7%)

  > 60

1652 (34.9%)

1129 (33.7%)

386 (37.0%)

137 (40.7%)

Employment status

 Permanent

2727 (57.7%)

1961 (58.6%)

586 (56.1%)

180 (53.4%)

 Temporary/contract

2003 (42.3%)

1388 (41.4%)

458 (43.9%)

157 (46.6%)

 PSQI

8.2 ± 3.9

7.4 ± 3.5

9.5 ± 3.9

11.8 ± 4.3

 PSQI> 5

3114 (65.8%)

2132 (63.7%)

725 (69.4%)

257 (76.3%)

 PSQI> 8

2905 (61.4%)

1998 (59.7%)

675 (64.7%)

232 (68.8%)