Table 3.
Crude and adjusted models describing the association of arm elevation (n = 118), trapezius activity (n = 94), and neck/shoulder load (n = 91) with NSPi, and the isotemporal substitutions estimating the change in NSPi when adding 30 min of exposure in the category at hand
| Arm elevation (n = 118) | Crude model | Adjusted modela | Isotemporal substitution estimates | |||||
|---|---|---|---|---|---|---|---|---|
| β | SE | p value | Β | SE | p value | Mean time course | + 30 min | |
| Intercept | 0.57 | 0.23 | 0.014 | 0.18 | 0.20 | 0.361 | 0.91 | |
| Time | 0.11 | 0.06 | 0.085 | 0.10 | 0.06 | 0.100 | 0.01 | |
| < 30° (vs > 30°) | 0.37 | 0.15 | 0.015 | 0.20 | 0.13 | 0.126 | 0.05 | |
| < 30° (vs > 30°)*time | − 0.07 | 0.04 | 0.089 | − 0.06 | 0.04 | 0.097 | − 0.01 | |
| 30–60° (vs < 30° and > 60°) | − 0.31 | 0.20 | 0.120 | − 0.22 | 0.16 | 0.161 | − 0.05 | |
| 30–60° (vs < 30° and > 60°)*Time | 0.03 | 0.05 | 0.539 | 0.03 | 0.05 | 0.534 | 0.02 | |
| > 60° (vs < 60°) | − 0.07 | 0.13 | 0.610 | 0.03 | 0.11 | 0.820 | 0.03 | |
| > 60° (vs < 60°)*time | − 0.06 | 0.05 | 0.243 | 0.03 | 0.03 | 0.324 | 0.03 | |
| Trapezius activity (n = 94) | Crude model | Adjusted modelb | Mean time course | + 30 min | ||||
|---|---|---|---|---|---|---|---|---|
| β | SE | p value | β | SE | p value | |||
| Intercept | 0.53 | 0.25 | 0.034 | 0.03 | 0.41 | 0.941 | 0.90 | |
| Time | 0.14 | 0.07 | 0.045 | 0.43 | 0.16 | 0.006 | 0.02 | |
| < 0.5%MVE (vs > 0.5%MVE) | − 0.26 | 0.13 | 0.041 | − 0.21 | 0.10 | 0.045 | − 0.09 | |
| < 0.5%MVE (vs > 0.5%MVE)*time | 0.03 | 0.04 | 0.327 | 0.05 | 0.03 | 0.113 | 0.04 | |
| 0.5–7.0%MVE (vs < 0.5% & > 7.0%MVE) | 0.30 | 0.22 | 0.173 | 0.32 | 0.18 | 0.072 | 0.08 | |
| 0.5–7.0%MVE (vs < 0.5% & > 7.0%MVE)*Time | − 0.13 | 0.06 | 0.040 | − 0.13 | 0.06 | 0.037 | − 0.01 | |
| > 7.0%MVE (vs < 7.0%MVE) | − 0.04 | 0.14 | 0.774 | − 0.11 | 0.11 | 0.330 | − 0.03 | |
| > 7.0%MVE (vs < 7.0%MVE)*time | 0.09 | 0.04 | 0.019 | 0.07 | 0.04 | 0.067 | 0.04 | |
| Neck/Shoulder(n = 91) | Crude model | Adjusted modelb | Mean time course | + 30 min | ||||
|---|---|---|---|---|---|---|---|---|
| β | SE | p value | β | SE | p value | |||
| Intercept | 0.48 | 0.25 | 0.057 | 0.09 | 0.40 | 0.819 | 0.89 | |
| Time | 0.17 | 0.07 | 0.022 | 0.40 | 0.16 | 0.010 | 0.02 | |
| Restitution (vs shoulder load) | − 0.28 | 0.10 | 0.008 | − 0.17 | 0.09 | 0.053 | −0.08 | |
| Restitution (vs shoulder load)*Time | 0.02 | 0.03 | 0.498 | 0.03 | 0.03 | 0.223 | 0.04 | |
| Low load (vs restitution, medium, high load) | 0.48 | 0.21 | 0.026 | 0.40 | 0.18 | 0.027 | 0.09 | |
| Low load (vs restitution, medium, high load)*Time | − 0.07 | 0.06 | 0.260 | − 0.09 | 0.06 | 0.132 | 0.00 | |
| Medium load (vs restitution, low, high load) | − 0.12 | 0.31 | 0.697 | − 0.17 | 0.25 | 0.510 | − 0.04 | |
| Medium load (vs restitution, low, high load)*Time | − 0.07 | 0.10 | 0.445 | −0.02 | 0.09 | 0.874 | 0.02 | |
| High load (vs restitution, low, medium load) | − 0.09 | 0.20 | 0.661 | − 0.06 | 0.16 | 0.536 | − 0.03 | |
| High load (vs restitution, low, medium load)*Time | 0.12 | 0.06 | 0.047 | 0.07 | 0.06 | 0.276 | 0.05 | |
Bold face mark associations with p < 0.05
aAdjusted for gender, sector, and NSP duration in the 12 months preceding baseline
bAdjusted for gender, sector, NSP duration in the 12 months preceding baseline, social climate, social climate*time, control of work pacing, control of work pacing*time
cAdjusted for sector and NSP duration in the 12 months preceding baseline, social climate, social climate*time, control of work pacing, control of work pacing*time