Table 4 Characteristics of subgroups after 2 years’ follow-up
From: Rotating shift work and menstrual characteristics in a cohort of Chinese nurses
Variables | Case group | Control group | P-value | ||
|---|---|---|---|---|---|
Shift (n = 45) | Shift controls (n = 67) | Non-shift controls (n = 30) | |||
Age (years); mean (SD), range, days | 27.4 (3.26), 22–35 | 28.7 (2.53), 24–34 | 27.2 (2.86), 23–34 | F = 3.60 | 0.050 |
BMI (kg/m2); mean (SD), range | 19.5 (1.50), 16.8–23.8 | 20.3(1.75);16.41-23.94 | 19.7 (2.07), 15.94–24.88 | F = 2.78 | 0.065 |
Duration of shift work (years); mean (SD), range | 5.2 (2.99), 2.5–9.0 | 6.1 (1.78), 3–10.5 | 4.2 (1.67), 2.0–8.0 | F = 13.3 | 0.000 |
Number of night shifts/month; mean (SD), range | 3.2 (1.39), 1.0–6.0 | 3.8 (1.29), 1.5–7.0 | –– | t = 1.71 | 0.089 |
Number of evening shifts/month; mean (SD), range | 4.5 (1.23), 2.5–7.5 | 3.7 (1.45), 1.5–8.0 | –– | t = 3.08 | 0.003 |
Sleep length (hours); mean (SD), range | 6.32 (1.47), 5–11 | 6.18 (1.23), 5–10.5 | 7.01 (1.65), 5.5–10 | F = 7.29 | 0.01 |
Standard SDS score; mean (SD), range | 37.8 (5.31), 26.0–48.75 | 36.4 (4.55), 26.25–47.50 | 35.0 (5.15), 23.75–42.50 | F = 3.02 | 0.052 |
Perceived job satisfaction; n (%) | |||||
Low | 5 (11.1 %) | 8 (11.9 %) | 0 | χ2 = 29.83 | 0.000 |
Medium | 37 (82.2 %) | 54 (80.6 %) | 16 (53.3 %) | ||
High | 3 (6.7 %) | 5 (7.5 %) | 14 (46.7 %) | ||