Table 1.
Baseline characteristics of a working population with shoulder disorders (n = 350), and univariable associations with sick leave (yes/no) during 6 months following first consultation in general practice
| Variable | n (%)@ | OR | 95% CI | pa |
| Demographic | ||||
| Age (years); mean (SD) | 45 (11) | 1.0 | 1.0, 1.0 | 0.26 |
| Gender: male | 193 (55) | 0.9 | 0.5, 1.4 | 0.56 |
| Education | 0.02 | |||
| Low* | 98 (28) | - | ||
| Middle | 148 (43) | 0.5 | 0.3, 0.9 | |
| High | 99 (29) | 0.4 | 0.2, 0.9 | |
| Disease characteristics | ||||
| Duration of complaints | 0.77 | |||
| 0–6 weeks* | 139 (40) | - | ||
| 7–12 weeks | 77 (22) | 1.1 | 0.6, 2.1 | |
| >3 months | 134 (38) | 0.9 | 0.5, 1.5 | |
| Sick leave at baseline in preceding 2 months | <0.001 | |||
| 0 weeks* | 254 (74) | - | ||
| ≤1 weeks | 44 (13) | 1.8 | 0.9, 3.9 | |
| >1 weeks | 46 (13) | 3.3 | 1.6, 6.9 | |
| Gradual onset (vs. acute) | 212 (61) | 1.0 | 0.6, 1.6 | 0.89 |
| Opinion regarding cause | ||||
| Unexpected movement | 16 (5) | 1.7 | 0.5, 5.6 | 0.36 |
| Strain/overuse: unusual activities | 56 (16) | 0.5 | 0.2, 1.1 | 0.08 |
| Strain/overuse: regular activities | 99 (28) | 2.4 | 1.4, 4.1 | <0.001 |
| Injury | 15 (4) | 4..4 | 1.4, 15.3 | 0.01 |
| Sport injury | 22 (6) | 0.5 | 0.1, 1.7 | 0.26 |
| Unknown | 133 (38) | 1.4 | 0.9, 2.4 | 0.17 |
| Shoulder complaints in the past | 199 (57) | 1.4 | 0.8, 2.3 | 0.19 |
| Neck complaints in the past | 165 (48) | 1.5 | 0.9, 2.4 | 0.11 |
| Dominant side involved | 210 (60) | 1.5 | 0.9, 2.4 | 0.15 |
| Co-existing psychological complaints | 27 (8) | 5.4 | 2.0, 13.9 | <0.001 |
| Additional musculoskeletal complaints | ||||
| Neck/high back | 119 (34) | 1.6 | 1.0, 2.7 | 0.07 |
| Low back pain | 61 (17) | 1.3 | 0.6, 2.4 | 0.50 |
| Upper extremity | 96 (27) | 1.4 | 0.8, 2.5 | 0.21 |
| Lower extremity | 77 (22) | 0.7 | 0.4, 1.3 | 0.30 |
| Shoulder pain (0–10); mean (SD) | 4.5 (2.3) | 0.01 | ||
| 0–3 points* | - | |||
| 4–6 points | 2.4 | 1.3, 4.5 | ||
| 7–10 points | 2.3 | 1.2, 4.5 | ||
| Shoulder disability (SDQ) (0–100); mean (SD) | 58.4 (24.0) | 1.9 | 0.8, 4.8 | 0.24 |
| Physical examination | ||||
| ROM shoulder (0–18) (median, IQR) | 3 (2–5) | 0.7# | 0.3, 1.6 | 0.74 |
| Pain shoulder with movement (<12, ≥ 12 points) | 6.3 (4.0) | 2.9# | 1.3, 6.7 | 0.03 |
| ROM neck (0–4) (median, IQR) | 0 (0–1.5) | 1.2# | 0.7, 2.2 | 0.41 |
| Pain neck with movement (0–18) (median, IQR) | 0 (0–3) | 1.1 | 1.0, 1.3 | 0.01 |
| Physical factors | ||||
| Physical work load (0–5) (median, IQR) | 1.6 (1.6) | 1.3 | 1.1, 1.5 | 0.01 |
| Repetitive movements (yes/no) | 279 (80) | 1.0 | 0.6, 1.9 | 0.97 |
| Sitting in static position for long duration (yes/no) | 138 (40) | 1.2 | 0.7, 1.9 | 0.54 |
| Physical activity in comparison to others | 0.09 | |||
| more active* | 130 (37) | - | ||
| equally active | 158 (45) | 1.5 | 0.9, 2.7 | |
| less active | 60 (17) | 2.2 | 1.1, 4.5 | |
| Psychological factors | ||||
| Coping; mean (SD) | ||||
| Catastrophizing (1–6) | 2.2 (0.8) | 1.6 | 1.1, 2.2 | 0.01 |
| Coping with pain (1–6) | 2.9 (1.0) | 2.6# | 0.4, 17.9 | 0.44 |
| Internal locus of control (1–6) | 3.4 (0.9) | 1.5# | 0.4, 5.5 | 0.76 |
| External locus of control (1–6) | 3.1 (0.9) | 1.9# | 0.3, 14.2 | 0.76 |
| 4DSQ (median, IQR) | ||||
| Distress (0–32) | 0 (0–2) | 4.4$ | 1.3, 15.5 | 0.01 |
| Depression (0–12)b | 0 (0-0) | - | ||
| Anxiety (0–24)b | 0 (0-0) | - | ||
| Somatization (0–32) | 2 (0–4) | 3.0$ | 1.0, 9.1 | 0.05 |
| Fear-avoidance (0–24); mean (SD) | 14.4 (5.0) | 1.1 | 1.0, 1.1 | 0.04 |
| Kinesiophobia (0–12); mean (SD) | 3.3 (3.4) | 1.7# | 0.5, 5.3 | 0.07 |
| Psychosocial work environment | ||||
| Quantitative job demands (5–20); mean (SD) | 12.8 (2.7) | 1.4# | 0.6, 3.0 | 0.68 |
| Skill discretion (5–20); mean (SD) | 15.3 (2.8) | 1.8& | 0.6, 5.3 | 0.57 |
| Decision authority (3–12); mean (SD) | 9.4 (1.8) | 0.8 | 0.7, 0.9 | <0.001 |
| Co-worker support (4–16); mean (SD) | 12.3 (2.0) | 10.1& | 1.1, 92.4 | 0.07 |
| Supervisor support (4–16); mean (SD) | 11.2 (2.5) | 2.0& | 0.9, 4.2 | 0.20 |
SD = standard deviation; IQR = Inter quartile range; ROM = Range of Motion; 4DSQ = Four-dimensional symptom questionnaire. aVariables with a univariable p-value ≤ 0.20 were selected for the multivariable analysis. bORs haven't been computed due to empty cells in the cross-tables. @or otherwise stated *Reference category. #In case of non-linear associations continuous variables were divided into categories. The table presents the Odds Ratio (OR) for the highest versus lowest category. &ORs were computed for lowest versus highest categories. $Variable was dichotomised. (lowest versus middle and high category).