Table 3. Effects (coefficients with standard errors [SE] and p-values) of group, time and group*time interaction on characteristics of working days, days off, scheduled absences, sickness absence days, length of working hours, shift intensity, recovery, and social aspects of working hours in intervention and control groups.
| Working days, days off, scheduled and sickness absence days | Group effect | Time effect | Interaction | |||||
|---|---|---|---|---|---|---|---|---|
| Coeffcient (SE) | p value* | Coeffcient (SE) | p value* | Coeffcient (SE) | p value* | |||
| Working d/3-wk period | 0.36 (0.12) | <0.001 | −0.34 (0.11) | <0.001 | 0.05 (0.12) | 0.665 | ||
| Days off/3-wk period1 | 0.08 (0.39) | 0.533 | −0.49 (0.07) | <0.001 | 0.28 (0.08) | <0.001 | ||
| Scheduled absence d/3-wk period2 | −0.27 (0.23) | 0.227 | 0.21 (0.11) | <0.001 | 0.28 (0.12) | 0.017 | ||
| Sickness absence d/yr3 | 6.51 (1.16) | <0.001 | 1.33 (1.25) | 0.002 | 1.66 (1.38) | 0.227 | ||
| Length of working hours | ||||||||
| Weekly working hours (h) | 1.36 (0.84) | 0.141 | 0.18 (0.15) | 0.581 | −0.27 (0.16) | 0.107 | ||
| % of long (> 40 h) working weeks | 1.69 (0.64) | 0.004 | 0.63 (0.56) | 0.077 | −0.18 (0.61) | 0.765 | ||
| % of long (> 48 h) working weeks | 0.97 (0.32) | 0.003 | 0.26 (0.29) | 0.094 | 0.03 (0.32) | 0.922 | ||
| Shift length (h) | 0.38 (0.13) | 0.002 | −0.00 (0.02) | 0.392 | 0.02 (0.02) | 0.295 | ||
| Shift intensity | ||||||||
| Number of consecutive working days | −0.01 (0.32) | 0.886 | 0.04 (0.02) | 0.440 | −0.07 (0.02) | 0.005 | ||
| % of long spells of work shifts | 0.33 (0.56) | 0.921 | 0.47 (0.14) | 0.009 | −0.55 (0.15) | <0.001 | ||
| Number of consecutive night shifts | 0.11 (0.41) | 0.905 | 0.13 (0.03) | 0.001 | −0.13 (0.03) | <0.001 | ||
| % of long spells of consecutive night shifts | 0.69 (1.29) | 0.826 | 0.84 (0.25) | <0.001 | −0.83 (0.27) | 0.002 | ||
| Recovery | ||||||||
| Time between shifts (h) | −0.19 (0.33) | 0.553 | −0.02 (0.06) | 0.489 | −0.01 (0.07) | 0.929 | ||
| % of short shift intervals | 1.89 (6.86) | 0.782 | −0.45 (0.40) | 0.044 | 0.01 (0.44) | 0.973 | ||
| % of short recovery periods after last night shift | −0.78 (0.86) | 0.290 | −2.53 (0.94) | 0.044 | 3.02 (1.01) | 0.003 | ||
| Social aspects of working hours | ||||||||
| % of annual leave days | 0.13 (1.10) | 0.966 | 1.03 (0.30) | <0.001 | −0.36 (0.33) | 0.284 | ||
| % of weekend work | 4.28 (7.79) | 0.621 | −0.90 (0.68) | <0.001 | −0.87 (0.75) | 0.245 | ||
| % of single days off | −1.92 (7.54) | 0.752 | 1.28 (0.43) | <0.001 | −0.92 (0.47) | 0.050 | ||
| Variability of shift starting times | 0.54 (0.07) | <0.001 | 0.09 (0.04) | 0.056 | −0.10 (0.04) | 0.023 | ||
| % of realized shift plans | −0.79 (0.39) | 0.010 | −0.16 (0.37) | 0.114 | −0.32 (0.41) | 0.425 | ||
| % of preferred shifts | −8.03 (9.43) | 0.344 | 1.69 (0.50) | 0.004 | −1.80 (0.56) | 0.001 | ||
| % of realized shift preferences | −3.42 (3.71) | 0.332 | 0.22 (0.24) | 0.761 | −0.36 (0.26) | 0.163 | ||
*Statistically significant p-values <0.05 in boldface. 1 Days off are scheduled days off (but not annual leave or anything else) within a three-week period; 2 Scheduled absences (sick leave, maternity leave, annual leave etc.) are planned into the scheduling programme for each three-wk period; 3 Sickness absence days include all days of absence (sudden or scheduled) due to sickness. Group effect reflects the difference between intervention and control group, time effect reflects difference between 2012 and 2013, and interaction is the time*group effect, reflecting the potential effect of the intervention.