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Table 1 Baseline characteristics of the study population (n = 1760)

From: Course and prognosis of recovery for chronic non-specific low back pain: design, therapy program and baseline data of a prospective cohort study

Variables Population (n = 1760) Missing value
Number of female participants 1307(74.3) 0
Age in years: M (SD) 40.1(10.6) 0
Weight (kg): M (SD)* 75.3(14.8) 81(4.6)
Height (cm): M (SD)* 172.2(8.8) 70(4.0)
Demographic factors   
Low education * 716(40.7) 71(4.0)
Marital status/living with one adult* 1515(86.1) 46(2.6)
Lifestyle   
Alcohol consumers; more than 2 per day* 73(4.1) 326(18.5)
Smoking 'yes' * 413(23.5) 326(18.5)
No drug consumers * 1399(79.5) 313(17.8)
Clinical status   
Patients with BMI > 25* 783(44.5) 88(5.0)
Duration of complaints in years: M (SD) 7.7(8.8) 0
1 gradual emergence of NLBP 1167(66.3) 30(1.7)
2 sudden emergence of NLBP 563(32.0)  
Cause   23(1.3)
1 accident/wrong movement 374(21.3)  
2 after physical overload 73(4.1)  
3 during pregnancy or after delivery 586(33.3)  
4 surgery pelvis/back or after HNP 32(1.8)  
5 unknown 672(38.2)  
Previous revalidation program* 186(10.6) 101(5.7)
Co-morbidity 275(15.6) 88(5.0)
VAS Pain intensity LBP in mm: M (SD)   
1 present pain intensity 55.5(23.0) 5(0.3)
2 minimal pain intensity 34.6(21.7) 13(0.7)
3 maximal pain intensity 80.0(16.2) 13(0.7)
Pain intensity due to CNLBP in the previous 3 months   52(3.0)
1 stable pain intensity 865(49.1)  
2 increased pain intensity 723(41.1)  
3 decreased pain intensity 120(6.8)  
VAS degree of fatigue LBP in mm: M (SD)   
1 present fatigue 56.5(26.6) 118(6.7)
2 minimal fatigue 32.2(23.3) 169(9.6)
3 maximal fatigue 77.8(20.4) 169(9.6)
Disability (QBPDS): M (SD) 51.7(15.6) 8(0.5)
Psychological factors   
Fear avoidance (TSK): M (SD) 36.7(7.3) 50(2.8)
SF-36 (health-related quality of life)   
PCS 31.8(7.1) 493(28.0)
MCS 46.5(10.3) 493(28.0)
Work-related factors   
Employment status benefit 924(52.5) 353(20.1)
Work participation   161(9.1)
1 100% working 391(22.2)  
2 1-99% working 488(27.7)  
3 not working 689(39.1)  
4 retired 31(1.8)  
Less work due to   460(26.1)
1 complaints 772(43.9)  
2 unemployed 19(1.1)  
3 different reasons 177(10.1)  
4 fully working 332(18.9)  
Physical examination   
LDL positive   
1 left 1373(78.0) 29(1.6)
2 right 1336(75.9) 31(1.8)
Mobility (VR) (degrees in flexion): M (SD)   
1 pelvis in flexion 40.7(15.7) 154(8.8)
2 low back in flexion 47.3(14.3) 154(8.8)
3 pelvis+low back in flexion (ROM) 88.0(24.6) 154(8.8)
ASLR positive (sum score ≥ 3)   
1 by general practitioner 1442(81.9) 16(0.9)
2 by patient 1217(69.1) 8(0.5)
ADL function - duration > 31 min without pain increase   
1 walking 410(23.3) 10(0.6)
2 cycling 312(17.8) 287(16.3)
3 sitting 432(24.5) 13(0.7)
4 lying 1017(57.8) 15(0.9)
5 standing 106(6.1) 9(0.5)
PPPP positive (uni or bilateral) 1110(63.1) 50(2.8)
Load transfer Abduction (Newton): M (SD) 224.9 (96.4) 137 (7.8)
Load transfer Adduction (Newton): M (SD) 172.5 (87.2) 136 (7.7)
B200 Isostation (strength) (Newton): M (SD)   
1 extension 81.6(45.8) 107(6.1)
2 flexion 65.2(45.0) 106(6.0)
3 lateroflexion left 68.1(41.2) 106(6.0)
4 lateroflexion right 74.2(39.4) 106(6.0)
5 rotation left 34.6(23.1) 107(6.1)
6 rotation right 33.4(22.5) 108 (6.1)
  1. Values are numbers (percentages) unless stated otherwise.
  2. * these factors were reported when therapy started, or gathered from the personal status; M = mean; SD = standard deviation; BMI = Body Mass Index; NLBP = non-specific low back pain; VAS = Visual analogue scale; QBPDS = Quebec Back Pain Disability Scale; TSK = Tampa Scale Kinesiophobia; SF-36 = Short Form; PCS = Physical Component Summary; MCS = Mental Component Summary; SCL-90 = Symptom Checklist; GPE = Global Perceived Effect; ADL = activities of daily living; VR = video registration; ASLR = Active Straight Leg Raise; PPPP = Posterior Pelvic Pain Provocation test; LDL = longum dorsal sacroiliac ligament.