Introduction 1999 2001 1998 1999 1997 2002a b 2001 1999 2000 2002 2000 2001 1996 1999 2000 2004 1996 2002 2004 2004 1997 2002 2000 Methods Design and study population 2003 2003 2003 Over a period of 1 year the GPs recruited 727 patients with a new complaint or new episode of a complaint at the neck, shoulder, elbow, arm, wrist or hand. An episode was considered to be ‘new’ if patients had not visited their GP for the same complaint during the preceding 3 months. Patients were eligible for participation if they were 18 years or older and capable of filling in Dutch questionnaires. Patients were excluded from the study if the presented symptoms were presumably caused by a fracture, malignancy, prosthesis, amputation or congenital defect or if the patient was pregnant. n n n n Outcome measure Sick leave was measured at 3 months after baseline by the question: “how long were you absent from work because of your complaint since the baseline questionnaire”. Response categories were (1) no sick leave; (2) less than 1 week; (3) between 1 and 2 weeks; (4) between 2 weeks and 1 month; (5) between 1 and 3 months; (6) more than 3 months. Sick leave was dichotomised into no sick leave (response category 1) and sick leave (response categories 2–6). Determinants 2004 2004 1979 1998 1998 Statistical analysis T 2 2003 1994 1998 1998 1 Table 1 Potential confounders of the association between work-related risk factors and sick leave in patients with neck or upper extremity complaints Potential confounders Categorization Individual factors  Age Continuous (per year)  Sex Male versus female  Smoking Present versus previous smoker  Education Primary versus secondary; college/university a Continuous (scale 7–28) a Continuous (scale 9–36)  Distress (six items) Continuous (scale 1–9) General health c Norm not met versus norm met  Norm healthy activity Norm not met versus norm met d Continuous (scale 1–5) d Continuous (scale 0–100)  Quality of life Continuous (scale 1–5) Characteristics of the complaint  Kind of complaint Localized versus generalized  Duration of the complaint Categorical (<1, 1–4 weeks; 1–6 , >6 months)  History of neck/upper limb complaints History versus no history  Musculoskeletal co-morbidity Yes versus no  Other co-morbidity Yes versus no Work-related psychosocial factors (%) f Tertiles (low, medium, high) f Tertiles (low, medium, high) f Tertiles (low, medium, high) f Low security versus high security  Job as perceived cause of complaint Yes versus no a 2003 1997 b 1998 c 1990 d 1992 e 2004 f 1998 P P P P P 1 P Individual factors may interact in the relation between work-related physical and psychosocial risk factors and sick leave. We considered possible effect modification by sick leave at baseline, sex, coping style worrying (dichotomized) and musculoskeletal co-morbidity. Product terms of the potential effect modifier and the work-related risk factor were added to the model (e.g., sex × risk factor). Furthermore, possible effect modification by psychosocial risk factors was investigated in the relation between the four physical risk factors and sick leave. Factors significantly interacting with determinants in the model were retained in the models. In case of significant effect modification stratified analyses were carried out presenting the effect of the work-related risk factor for relevant subgroups of workers. All analyses were performed with the use of SPSS for Windows version 10.1 (SPSS Inc., Chicago, IL, USA).
 Results P n n 2 Table 2 n n Characteristic a a Total Individual factors  Age, years [mean (SD)] 42.0 (11.5) 43.6 (9.8) 43.0 (10.3)  Sex (female) 75% 49%** 54%  Sick leave in 3 months before baseline 59% 16%** 25%  Education level   Primary 48% 30%* 34%   Secondary 40% 49% 48%   College/university 12% 21% 18%  Number of hours work (h)      8–16 11% 12% 11%   17–24 18% 25% 20%   25–36 26% 30% 27%   >36 45% 33% 42% Married/living together 63% 83%* 78% Smoking (now, ever) 77% 67% 70% Pain coping: retreating [scale 7–28; median (IR)] 11.0 (5.0) 9.0 (4.8)** 10.0 (4.5) Pain coping: worrying (scale 9–36; median (IR)) 18.0 (7.0) 14.0 (5.0)** 15.0 (6.0) Psychological distress (scale 0–12; median (IR)) 7.0 (5.0) 4.0 (5.0)** 5.0 (6.0) General health  Meeting ACSM position stand 4% 16%* 13%  Meeting Norm Healthy Activity 41% 42% 43%  Perceived health [scale 1–5; mean (SD)] 3.1 (0.8) 3.4 (0.9)* 3.3 (0.8)  Quality of life [scale 1–5; mean (SD)] 3.2 (0.7) 3.5 (0.8)* 3.4 (0.8)  Vitality [scale 0–100; mean (SD)] 54.3 (20.9) 62.4 (17.2)** 60.0 (18.5) Characteristics complaint  Localized complaint 40% 53%* 49%  Complaint at both arms 10% 15% 13%  Complaint at dominant arm 50% 44% 47% Duration of current episode  <1 week 5% 7% 7%  1week–1 month 36% 32% 33%  1–6 months 29% 37% 34%  >6 months 30% 24% 26% History of elbow complaints 51% 43% 45% Musculoskeletal co-morbidity 56% 47% 50% Pain intensity [scale 0–10; mean, (SD)] 6.0 (1.9) 4.4 (2.1)** 4.8 (2.2) Functional disability [scale 0–100; median (IR)] 36.3 (28.8) 16.5 (21.3)** 20.0 (25.3) Work-related factors  Heavy physical work [scale 0–100; mean (SD)] 36.1 (40.2) 16.7 (36.1)** 22.2 (42.8)  Static postures and repetitive movements (scale 0–100) 55.6 (47.2) 44.4 (44.4)** 44.4 (38.9)  Sitting for a long period of time 22% 48%** 42% VDU-work for a long period of time 21% 36%* 31%  Decision authority [scale 3–12; mean (SD)] 9.0 (3.0) 9.0 (3.0)* 9.0 (3.0)  Job demands [scale 5–20; mean (SD)] 13.4 (3.6) 12.8 (2.9) 12.9 (3.1)  Co-worker support [scale 4–16; mean (SD)] 12.0 (1.0) 12.0 (2.0) 12.0 (2.0)  Job security 78% 85% 83%  Job as perceived cause of complaint 62% 49% 56% VDU SD IR P P T 2 a 3 P P Table 3 Relationship between work-related risk factors and sick leave in patients with neck or upper extremity complaints: results from the multiple Cox regression analyses Determinant N Crude HR 95% CI Adjusted HR 95% CI Heavy physical work (per 10% increase) 69/320 1.23 [1.12; 1.36]*   d 21/140   1.05 a d 48/180   1.32 a, Static postures, repetitive movements (per 10% increase) 69/320 1.16 [1.06; 1.27]* 1.04 b Sitting for long periods of time (vs. never/now and then) 16/322 0.40 [0.23; 0.70]*   d 2/180   0.81 a d 14/142   0.17 a, VDU-work long periods of time (vs. never/now and then) 15/322 0.56 [0.32; 1.00]* 0.70 c Decision authority  Low  1.00     Medium  0.80 [0.47; 1.35] 0.94 a  High  0.59 [0.31; 1.13] 0.87 a Job demands  Low 23/115 1.00  1.00   Medium 20/111 0.90 [0.49; 1.64] 0.91 a  High 27/95 1.42 [0.81; 2.48] 1.13 a Co-worker support  Low 16/86 1.00  1.00   Medium 31/140 1.19 [0.65; 2.18] 1.22 a  High 23/88 1.40 [0.74; 2.66] 1.14 a Low job security (vs high) 70/319 1.43 [0.78; 2.60] 1.47 a Job strain  High decision authority, low job demands 10/77 1.00  1.00   High decision authority, high job demands 11/52 1.63 [0.69; 3.84] 1.29 b  Low decision authority, low job demands 25/104 1.85 [0.89; 3.85] 1.30 b  Low decision authority, high job demands  24/86 2.15 [1.03; 4.49]* 1.15 b N HR P a b c d Discussion We studied a population of working employees who consulted their GP with a complaint at the neck or upper extremity. The results show that heavy physical work and prolonged sitting in patients that worry a lot predicted sick leave in the three successive months after baseline. Other physical and psychosocial risk factors appeared not to be related to sick leave after adjustment for confounding variables. 2000 2003 2002b 2002 1996 1998 1996 Our study population differs from an occupational cohort, consisting of workers from a wide variety of occupational settings who had visited the GP due to neck or upper extremity complaints. This makes our results more widely generalisable than a selective sample of workers from a specific company or industry. However, due to the fact that our population already had symptoms at baseline we may not be able to discriminate between factors that are a consequence of sick leave at baseline and factors that may increase the risk of sick leave. For example, patients may worry more about their pain problem because they are no longer able to work, or worrying about their pain problem may be the reason for sick leave after their visit to the doctor. In the Netherlands the GP is often confronted with patients who are on sick leave due to musculoskeletal complaints, as patients who seek medical care usually first consult their GP. The GP acts as a gatekeeper in the health care system. At the time of our study, referrals to the second or third level of care could, in principle, only be made by the GP. This is comparable to, for instance, the British and the Canadian health care systems. As a result of their position in the Dutch health care system, GPs could play an important role in the prevention of aggravation of complaints. In this study the copying style “worrying” seemed to be an important factor in patients who have jobs involving heavy physical work. Reassuring patients might help to reduce aggravation of complaints, which might improve the chances of return to work in this group of patients with neck or upper extremity complaints. It may be interesting to investigate whether early intervention aimed at promoting particular coping styles can prevent or reduce sick leave in patients with neck or upper extremity complaints in a primary care setting. In conclusion, heavy physical work increased the risk of sick leave and prolonged sitting reduced the risk of sick leave in a subgroup of patients who worry much. Other work-related physical risk factors and work-related psychosocial risk factors were not significantly related to sick leave. Additional large longitudinal studies of sufficiently large size among employees with neck or upper extremity complaints are needed to confirm our results.