Table 1 Participant characteristics at baseline
|  | Total population (n = 239) | Subgroup Baseline duration < 3 mo (n = 133)a | Subgroup Baseline duration ≥3 mo (n = 101)a | p-value |
|---|---|---|---|---|
Variables | Number of participants (%)b | %b | %b | Â |
Participant characteristics | ||||
 Gender (female), n (%) | 177 (74) | 79.7 | 68.3 | 0.047 |
 Age(years),mean (sd) | 35.5 (13.3) | 30.9 (12.17) | 44.1 (11.2) | < 0.001 |
 Body mass index (kg/m2), mean (sd) | 23.9 (3.37) | 23.4 (3.27) | 24.5 (3.37) | 0.026 |
 Paid work, n (%) | 149 (62) | 39.8 | 91.1 | < 0.001 |
 Student status, n (%) | 89 (38) | 60.2 | 8.9 |  |
 Scientific staff, n (%) | 60 (42.3) | 49.1 | 38.2 | 0.205 |
 Support staff, n (%) | 82 (57.7) | 50.9 | 61.9 |  |
 Marital status |  |  |  | < 0.001 |
  Unmarried/ living alone, n (%) | 68 (28) | 49.5 | 19.7 |  |
  Married/ living together, n (%) | 110 (46) | 47.7 | 72.4 |  |
  Widow/ divorced, n (%) | 9 (4) | 2.8 | 7.9 |  |
  Unknown, n (%) | 52 (22) |  |  |  |
 Children in the household |  |  |  | 0.312 |
  No, n (%) | 163 (68) | 89.7 | 82.9 |  |
  Yes, one or more, n (%) | 24 (10) | 10.3 | 17.1 |  |
  Unknown, n (%) | 52 (22) |  |  |  |
Health behaviour | ||||
 Currently smoking |  |  |  | 0.063 |
  No, I have never smoked, n (%) | 119 (50) | 72.0 | 53.9 |  |
  No, but I used to smoke now and then n (%), | 22 (9.2) | 11.2 | 13.2 |  |
  No, but I used to smoke every day, n (%) | 24 (10) | 10.3 | 17.1 |  |
  Yes, I smoke now and then, n (%) | 3 (1) | 1.9 | 1.3 |  |
  Yes, I smoke every day, n (%) | 16 (7) | 4.7 | 14.5 |  |
  Unknown, n (%) | 55 (23) | – | – |  |
 Alcohol consumption |  |  |  | 0.134 |
  No, never or seldom, n (%) | 50 (21) | 27.1 | 27.6 |  |
  Yes, now and then (< 3 drinks/week), n (%) | 89 (37) | 53.3 | 40.8 |  |
  Yes, >  3 drinks/ week, n (%) | 45 (19) | 19.6 | 31.6 |  |
  Unknown, n (%) | 55 (23) | – | – |  |
Complaint characteristics | ||||
 Duration of current episode |  | – | – | – |
   <  1 month, n (%) | 112 (46.9) |  |  |  |
  1–3 months, n (%) | 21 (8.8) |  |  |  |
  3–6 months, n (%) | 19 (7.9) |  |  |  |
   > 6 months n (%) | 82 (34.3) |  |  |  |
  Unknown | 5 |  |  |  |
 History of CANS |  |  |  | < 0.001 |
  No, n (%) | 22 (9.2) | 19.4 | 9.3 |  |
  Yes, one time before, n (%) | 17 (7.1) | 20.9 | 3.1 |  |
  Yes, more times before, n (%) | 125 (52.3) | 59.7 | 87.6 |  |
 Discomfort of complaints |  |  |  | < 0.001 |
  No discomfort, n (%) | 1 (0.4) | 1.4 | 0.0 |  |
  Regularly, n (%) | 120 (50.2) | 86.8 | 61.6 |  |
  Almost continuously, n (%) | 46 (19.2) | 11.8 | 38.4 |  |
Baseline scores of outcome measures | ||||
 Complaints intensity in previous week (VAS) [0–10] mean (sd) | 4.05 (2.28) | 3.7 | 4.5 | 0.019 |
  median [range] | 4 [0–8] |  |  |  |
 Disability (DASH) [0–100] mean (sd) | 15.05 (12.5) | 11.7 (10.5) | 19.5 (13.8) | < 0.001 |
  median [range] | 13.36 [0.00–58.62] |  |  |  |
 Impact on participation and autonomy (IPA), | ||||
  Autonomy indoors [0–4], mean (sd) | 0.18 (0.33) | 0.15 (0.30) | 0.23 (0.37) | 0.085 |
  Family role [0–4] mean (sd), | 0.51 (0.59) | 0.38 (0.46) | 0.66 (0.65) | 0.001 |
  Autonomy outdoors [0–4], mean (sd) | 0.58 (0.62) | 0.47 (0.53) | 0.69 (0.69) | 0.019 |
  Social life and relationships [0–4], mean (sd) | 0.45 (0.48) | 0.41 (0.45) | 0.50 (0.52) | 0.214 |
  Work and education [0–4], mean (sd) | 0.86 (0.71) | 0.71 (0.69) | 1.03 (0.68) | 0.005 |
Physical activity in leisure time | ||||
 Sports participation (yes),n (%) | 117 (49) | 48.9 | 42.0 | 0.297 |
 NNGB (yes), n (%) | 239 (100) | 64.7 | 63.0 | 0.794 |
 VDU use > 2 h/day (yes), n (%) | 73 (31.5) | 42.9 | 16.2 | < 0.001 |
 Heavy physical load (0–8), mean (sd) | 3.05 (1.6) | 2.47 (1.3) | 2.92 (1.6) | 0.217 |
 Static physical load (0–2), mean (sd) | 1.41 (0.6) | 1.31 (0.5) | 1.50 (0.6) | 0.463 |
Psychosocial characteristics | ||||
 Social support, (SOS) [1–5], mean (sd) | 4.69 (0.5) | 4.20 (0.6) | 3.81 (0.59) | < 0.001 |
 Catastrophizing, (PCS) [0–52], mean (sd) | 9.81 (8.4) | 9.07 (8.4) | 10.61 (8.4) | 0.229 |
 Fear avoidance, (FABQ) | ||||
  Physical Activity subscale [0–24], mean (sd) | 8.81 (5.5) | 7.86 (5.4) | 9.99 (5.5) | 0.011 |
  Work subscale [0–42], mean (sd) | 15.43 (7.9) | 14.64 (6.8) | 15.89 (8.7) | 0.428 |
Work variables for working population (n = 149) | ||||
 Full-time work, n (%) | 111 (74.5) | 66.0 | 72.5 | 0.412 |
 Working less than 3 y in current job, n (%) | 41 (27.5) | 43.4 | 24.2 | 0.016 |
 Work-related complaints (yes), n (%) | 127 (85.2) | 88.3 | 87.4 | 0.859 |
 Sickness absence related to CANS |  |  |  | 0.185 |
  No, n (%) | 135 (93.1) | 98.1 | 90.2 |  |
  Yes, <  1 mo, n (%) | 8 (5.5) | 1.9 | 7.6 |  |
  Yes, ≥ 1 mo, n (%) | 2 (1.4) | 0 | 2.2 |  |
 Physical workload, (short version PWQ) | ||||
  Heavy physical load [7–14], mean (sd) | 7.20 (0.7) | 7.13 (0.4) | 7.26 (0.84) | 0.346 |
  Static repetitive load [8–16], mean (sd) | 13.65 (2.1) | 13.72 (2.4) | 13.68 (1.8) | 0.929 |
 Psychosocial factors for working population, (JCQ) | ||||
  Psychological job demands [5–20], mean (sd) | 11.3 (3.0) | 11.7 (3.1) | 11.0 (2.9) | 0.231 |
  Decision authority ([3–12]), mean (sd) | 9.5 (1.8) | 9.3 (1.6) | 9.3 (1.8) | 0.246 |
  Skill discretion [6–24], mean (sd) | 18.9 (3.0) | 18.9 (3.1) | 18.9 (2.9) | 0.996 |
  Co-worker support [4–16], mean (sd) | 11.5 (3.3) | 11.9 (3.6) | 11.2 (3.1) | 0.268 |
  Supervisor support [4–16], mean (sd) | 13.2 (2.1) | 13.6 (2.2) | 13.0 (2.09) | 0.176 |