Table 1

Characteristics of the sample, absolute numbers and proportions in per cent, N (%)
Whole Sample Insomniacs Non-insomniacs p (Chi2)
N = 2873 N = 342 (11.9%) N = 2531 (88.1%)
Individual characteristics
Female 1426 (49.6%) 229 (67.0%) 1197 (47.3%) 0.000
Mean age (SD) 59.97 (SD 7.7) 60.32 (SD 7.5) 59.92 (SD 7.8)
Economic activity
Employed 1157 (40.3%) 113 (33.0%) 1044 (41.2%) 0.000
Economically inactive 379 (13.2%) 68 (19.9%) 311 (12.3%)
Retired 1168 (40.7%) 133 (38.9%) 1035 (40.9%)
Unemployed 169 (5.9%) 28 (8.2%) 141 (5.6%)
Education
≥ 18 yrs. 297 (10.3%) 18 (5.3%) 279 (11.0%) 0.000
14-17 yrs. 666 (23.2%) 46 (13.5%) 620 (24.5%)
11-13 yrs. 1576 (54.9%) 198 (57.9%) 1378 (54.4%)
≤ 10 yrs. 334 (11.6%) 80 (23.4%) 254 (10.0%)
Income
Lowest (first quartile) 735 (25.6%) 111 (32.5%) 624 (24.7%) 0.002
Social isolation
Social Integration Index Level I 215 (7.5%) 47 (13.7%) 168 (6.6%) 0.000
Change of residence
Never 2317 (80.6%) 275 (80.4%) 2042 (80.7%) 0.905
Ever 556 (19.4%) 67 (19.6%) 489 (19.3%)
Neighbourhood contextual characteristics
Mean unemployment rate
Lowest (first quartile) 682 (23.7%) 60 (17.5%) 622 (24.6%) 0.004
Mid-low (second quartile) 738 (25.7%) 79 (23.1%) 659 (26.0%)
Mid-high (third quartile) 779 (27.1%) 106 (31.0%) 673 (26.6%)
Highest (forth quartile) 674 (23.5%) 97 (28.4%) 577 (22.8%)
High residential turnover
Never 2218 (77.2%) 251 (73.4%) 1967 (77.7%) 0.104
At some time 544 (18.9%) 72 (21.1%) 472 (18.6%)
All the time 111 (3.9%) 19 (5.6%) 92 (3.6%)
Mean years having lived under high noise at night time (SD) 0.49 (SD 2.05) 0.62 (SD 2.30) 0.47 (2.01) 0.184*

* t-test.

Riedel et al.

Riedel et al. BMC Public Health 2012 12:810   doi:10.1186/1471-2458-12-810

Open Data