Table 1.
Demographic data on female preschool teachers and randomly selected women as population controls
| Preschool cohort (total n = 4718)a | Population controls (total n = 4122)a | p valueb | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Median (IQR) | n/total n | % | (95% CI) | Median (IQR) | n/total n | % | (95% CI) | ||
| Age in years | 45 (38–53) | 48 (39–57) | < 0.0001 | ||||||
| Employment status (currently working) | 4265/4714 | 90 | (90–91) | 3310/4114 | 80 | (79–82) | < 0.0001 | ||
| Education and income combined (mutually exclusive categories)c | < 0.0001 | ||||||||
| University education and ≥ 30,000 SEK | 3804/4653 | 82 | (81–83) | 1774/4027 | 44 | (43–46) | |||
| No university education and ≥ 30,000 SEK, or, university education and < 30,000 SEK | 849/4653 | 18 | (17–19) | 1528/4027 | 38 | (36–39) | |||
| Lower than university education and < 30,000 SEK | 0/4653 | 0 | – | 725/4027 | 18 | (17–19) | |||
| Smoking (ever smoked daily) | 1213/4703 | 26 | (25–27) | 1591/4089 | 39 | (37–40) | < 0.0001 | ||
| Family history of hearing loss (< age 55) | 881/4702 | 19 | (18–20) | 755/4100 | 18 | (17–20) | 0.698 | ||
| Ear infections (recurrent or prolonged) | 728/4690 | 16 | (14–17) | 580/4092 | 14 | (13–15) | 0.077 | ||
| Tympanostomy tube (ever) | 191/3351 | 6 | (5–6) | 149/2743 | 5 | (5–6) | 0.651 | ||
| Noisy leisure activities (≥ month or more) | 1179/4705 | 25 | (24–26) | 1199/4089 | 29 | (28–31) | < 0.0001 | ||
| Hearing protection leisure time (always or often)d | 208/1164 | 18 | (16–20) | 233/1182 | 20 | (17–22) | 0.253 | ||
| Loud music in headphones (≥ month, ≥ 75% vol.) | 358/2695 | 13 | (12–15) | 460/2458 | 19 | (17–20) | < 0.0001 | ||
| Loud noise, can´t hear conversation (≥ 25% time) | 3368/4515 | 75 | (73–76) | 1176/3688 | 32 | (30–33) | < 0.0001 | ||
| Loud noise, have to raise own voice (≥ 25% time) | 3376/4517 | 75 | (73–76) | 1078/3689 | 29 | (28–31) | < 0.0001 | ||
| Hearing protection at work (always or often) | 123/4521 | 3 | (2–3) | 170/3698 | 5 | (4–5) | < 0.0001 | ||
| Changed job/workplace due to noise (ever) | 312/4685 | 7 | (6–7) | 72/4034 | 2 | (1–2) | < 0.0001 | ||
| Stressful working conditions | |||||||||
| Effort–reward imbalance (ERI) (ratio > 1) | 3725/4684 | 80 | (78–81) | 2383/4012 | 59 | (58–61) | < 0.0001 | ||
| Emotional demands, COPSOQ (often or always) | 1699/4663 | 36 | (35–38) | 919/3985 | 23 | (22–24) | < 0.0001 | ||
| Exposure strata among currently workinge | < 0.0001 | ||||||||
| Unexposed to noise and stress | 384/4205 | 9 | (8–10) | 919/3250 | 29 | (27–30) | |||
| Stress only (ERI or COPSOQ) | 831/4205 | 20 | (19–21) | 1483/3250 | 46 | (44–48) | |||
| Noise only (exposed ≥ 25% of time at work) | 294/4205 | 7 | (6–8) | 163/3250 | 5 | (4–6) | |||
| Both noise and stress exposure | 2696/4205 | 64 | (63–66) | 685/3250 | 21 | (20–22) | |||
IQR inter-quartile range
aTable shows data for subjects with non-missing data
bp values based on non-parametric test of difference in medians or Chi square test of difference in proportions between the two cohorts
cAll preschool teachers have a university degree and data was obtained from national registry. For controls, the proportion reporting university as the highest attained education level are shown. The rest had compulsory schooling or lower
dProportion of non-missing data among those reporting noisy leisure activities
eExclusive categories among currently working respondents excluding individuals with missing data on noise and/or stress exposure