Background
Trial objectives
Methods
Trial design and participants
Intervention
Control
Outcomes
Electronic patient record data
Patient questionnaire data
Changes to the protocol
Sample size
Statistical methods
Results
Baseline characteristics
Characteristics | Intervention (n = 212) | Control (n = 203) | missing %(n) | P value for difference between intervention and control groups |
---|---|---|---|---|
Agea (years) | 41.4 (12.8) | 44.6 (12.6) | 0 (0) | 0.011 |
Gender femaleb | 60.8 (129) | 67.0 (136) | 0 (0) | 0.193 |
Physically inactiveb (light exercise ≤ 1/month) | 4.8 (7) | 3.7 (6) | 26.3 (109) | 0.778 |
Body mass indexa (kg/m2) | 27.8 (5.8) | 27.8 (5.2) | 26.3 (109) | 0.984 |
Smokingb | 29.0 (42) | 29.8 (48) | 26.3 (109) | 0.871 |
DEPS scorec | 5.0 (8.0) | 6.0 (8.5) | 26.3 (109) | 0.118 |
Actively workingb | 57.9 (84) | 56.5 (91) | 26.3 (109) | 0.804 |
Work abilityc (0–10) | 7.0 (8.0) | 7.0 (8.0) | 26.3 (109) | 0.279 |
Comorbidity b | 26.9 (112) | |||
Diabetes | 3.5 (5) | 9.3 (15) | 0.062 | |
Rheumatoid arthritis | 1.4 (2) | 1.9 (3) | 1.000 | |
Spondylarthritis | 0 | 0.6 (1) | 1.000 | |
Osteoarthritis | 18.2 (26) | 25.5 (41) | 0.130 | |
Depression | 17.5 (25) | 22.4 (36) | 0.317 | |
Fibromyalgia | 2.1 (3) | 3.1 (5) | 0.727 | |
Inflammatory bowel disease | 1.4 (2) | 5.0 (8) | 0.110 | |
Muscle disease | 0.7 (1) | 0 | 0.470 |
Characteristics | Intervention (n = 212) | Control (n = 203) | P-value for the difference between intervention and control groups | Missing^^ in intervention %(n) | Missing^^ in control %(n) |
---|---|---|---|---|---|
Electronic patient records data | |||||
First contacting professional^ % (n)2 | 0.001 | 10.8 (23) | 9.4(19) | ||
Physician | 44.4 (84) | 27.7 (51) | |||
Nurse and physician | 12.2 (23) | 9.2 (17) | |||
Physiotherapist | 43.4 (83) | 62.0 (114) | |||
Nurse alone | 0.0 (0) | 1.1 (2) | |||
Baseline questionnaire data | |||||
Back pain intensity during past week1 (NRS, 0–10) | 5.1 (2.4) | 4.9 (2.5) | 0.455 | 31.6 (67) | 20.7 (42) |
Leg pain intensity during past week1 (NRS 0–10) | 3.7(3.3) | 3.3 (3.0) | 0.376 | 31.6 (67) | 20.7 (42) |
SBT total score1 | 4.5 (2.3) | 4.6 (2.3) | 0.702 | 31.6 (67) | 20.7 (42) |
SBT risk groups2 | 0.731 | 31.6 (67) | 20.7 (42) | ||
Low risk2 | 37.2 (54) | 32.9 (53) | |||
Medium2 | 40.0 (50) | 42.9 (69) | |||
High2 | 22.8 (33) | 24.2 (39) | |||
ÖMPSQ-short total score1 | 43.0 (17.3) | 43.2 (19.6) | 0.914 | 31.6 (67) | 20.7 (42) |
ÖMPSQ-short risk groups*2 | 0.615 | 31.6 (67) | 20.7 (42) | ||
Low risk2 | 48.3 (70) | 44.1 (71) | |||
Medium2 | 18.6 (27) | 17.4 (28) | |||
High2 | 33.1 (48) | 38.5 (62) | |||
Pain-related fear (FABQ)3 | 34.0 (29.5) | 37.0 (36.5) | 0.249 | 31.6 (67) | 20.7 (42) |
Pain-related fear (FABQ) -Work**3 | 13.0 (17.0) | 16.0 (21.5) | 0.213 | ||
Pain-related fear (FABQ) -Physical activity***3 | 13.0 (8.0) | 14.0 (9.5) | 0.773 | ||
Pain Self-Efficacy beliefs Questionnaire (PSEQ)3 | 44.0 (18.0) | 45.0 (20.0) | 0.908 | 31.6 (67) | 20.7 (42) |
Physical functioning (PROMIS PF-20 T-score)1 | 44.7 (6.7) | 43.8 (7.4) | 0.271 | 34.3 (73) | 25.1 (51) |
Physical impairment, (RMDQ)3 | 5.0 (7.0) | 6.0 (8.0) | 0.049 | 37.3 (79) | 29.6 (60) |
Disability (ODI%)1 | 23.9 (8.4) | 24.1 (8.9) | 0.832 | 31.6 (67) | 20.7 (42) |
Self-rated health status1 (1–100) | 67.1 (21.1) | 67.2 (20.8) | 0.953 | 31.9 (68) | 20.7 (42) |
LBP frequence (daily LBP yes/no)2 | 43.4 (63) | 50.9 (82) | 0.191 | 31.6 (67) | 20.7 (42) |
Duration of LBP2 | 0.586 | 31.6 (67) | 20.7 (42) | ||
3 weeks or less | 31.7 (46) | 33.5 (54) | |||
4 to 52 weeks | 44.8 (65) | 47.8 (77) | |||
over one year | 23.4 (35) | 18.6 (30) | |||
Pain medication use ≥ 3 days during past week2 | 46.9 (68) | 46.0 (74) | 0.870 | 31.6 (67) | 20.7 (42) |
Intervention results
Primary outcomes
Intervention group n = 178 | Control group n = 186 | intervention vs control | Age adjusted intervention vs control | |
---|---|---|---|---|
%(n) | %(n) | OR (95% CI); P value | OR (95% CI); P value | |
Imaginga (yes/no) | ||||
3 months | 10.8 (19) | 16.7 (31) | 0.57 (0.27 to 1.22); 0.147 | 0.60 (0.29–1.24); 0.166 |
12 months | 17.5 (31) | 29.7 (54) | 0.50 (0.30 to 0.83); 0.008 | 0.52 (0.32 to 0.84); 0.007 |
Radiographsa | ||||
3 months | 5.6 (10) | 9.1 (17) | 0.57 (0.25 to 1.29); 0.178 | 0.58 (0.25–1.33); 0.199 |
12 months | 8.4 (15) | 14.7 (27) | 0.55 (0.34 to 0.88); 0.013 | 0.58 (0.37 to 0.90); 0.016 |
Magnetic resonance imaging (MRI) a | ||||
3 months | 7.3 (13) | 8.6 (16) | 0.86 (0.49 to 1.52); 0.610 | 0.90 (0.55–1.48); 0.688 |
12 months | 12.8 (23) | 21.1 (39) | 0.61 (0.44 to 0.84); 0.002 | 0.64 (0.49 to 0.84); 0.001 |
Computed tomography (CT) a | ||||
3 months | 0 (0) | 1.6 (3) | c | c |
12 months | 0.6 (1) | 2.2 (4) | c | c |
MRI + CTa | ||||
3 months | 7.3 (13) | 9.1 (17) | 0.81 (0.45 to 1.46);0.475 | 0.86 (0.51–1.4); 0.555 |
12 months | 13.4 (24) | 21.7 (40) | 0.60 (0.39 to 0.91); 0.016 | 0.64 (0.45 to 0.91); 0.014 |
mean(SD); sum | mean(SD); sum | RR (95% CI); P-value | RR (95% CI); P-value | |
Sick leave daysb | ||||
3 months | 3.8 (11.2); 664 | 8.4 (20.2); 1526 | 0.47 (0.26 to 0.83); 0.010 | 0.48 (0.29 to 0.81); 0.006 |
12 months | 7.5 (31.3); 1330 | 20.8 (59.2); 3717 | 0.36 (0.18 to 0.72); 0.004 | 0.39 (0.22–0.70); 0.002 |
Physician appointments b | ||||
3 months | 1.1 (1.4); 156 | 1.2 (1.5); 188 | 0.92 (0.44 to 1.9); 0.813 | 0.92 (0.44 to 1.9); 0.822 |
12 months | 1.6 (2.1); 231 | 1.8 (2.3); 283 | 0.87 (0.4 to 1.9); 0.725 | 0.87 (0.41 to 1.78); 0.678 |
Physiotherapist appointmentsb | ||||
3 months | 1.2 (1.7); 212 | 1.3 (1.1); 235 | 0.88 (0.56 to 1.40); 0.601 | 0.89 (0.55 to 1.43); 0.618 |
12 months | 1.7 (2.6); 297 | 2.0 (2.2); 359 | 0.83 (0.55 to 1.2); 0.356 | 0.83 (0.56 to 1.23); 0.829 |
Nurse appointmentsb | ||||
3 months | 0.3 (1.2); 60 | 0.2 (0.7); 41 | 1.3 (0.20 to 8.42); 0.772 | 1.3 (0.20 to 9.69); 0.749 |
12 months | 0.6 (1.8); 107 | 0.3 (1.0); 60 | 1.72 (0.34 to 8.66); 0.514 | 1.93 (0.34 to 11.04); 0.458 |
Secondary health care appointments (physiatrist + orthopedist)b | ||||
3 months | 0.3 (1.0); 48 | 0.3 (0.7); 55 | 1.06 (0.68 to 1.65); 0.801 | 1.10 (0.73 to 1.64); 0.662 |
12 months | 0.6 (1.6); 87 | 0.7 (1.8); 132 | 0.81 (0.49 to 1.35); 0.426 | 0.84 (0.53 to 1.33); 0.447 |
Outcome | Time | Intervention group n (total n = 145) | Control group n (total n = 161) | Intervention group Meana (SE) | Control group Meana (SE) | Mean differenceb (95% CI) | P value | Age-adjusted mean differenceb (95% CI) | P value |
---|---|---|---|---|---|---|---|---|---|
PROMIS T-scoreb | Baseline | 139 | 152 | 44.7 (0.6) | 43.8 (0.6) | 0.9 (-0.7 to 2.6) | 0.271 | 0.5 (-1.1 to 2.1) | 0.526 |
Change 3 m | 84 | 95 | 2.5 (0.7) | 1.5 (0.7) | 1.0 (-1.5 to 3.5) | 0.365 | 0.93 (-1.0 to 2.9) | 0.346 | |
Change 12 m | 67 | 91 | 2.2 (0.9) | 2.3 (0.7) | -0.1 (-2.3 to 2.1) | 0.923 | 0.09 (-2.3 to 2.2) | 0.935 | |
Low back pain intensity during last week (NRS, 0–10) b | Baseline | 145 | 161 | 5.1 (0.3) | 4.8 (0.3) | 0.29 (-0.8 to 1.3) | 0.521 | 0.38 (-0.7 to 1.5) | 0.427 |
Change 3 m | 91 | 105 | -0.6 (0.5) | -0.4 (0.5) | -0.3 (-2.1 to 1.5) | 0.732 | -0.3 (-2.1 to 1.5) | 0.695 | |
Change 12 m | 79 | 105 | -1.8 (0.5) | -1.3 (0.5) | -0.47 (-2.1 to 1.2) | 0.517 | -0.5 (-2.2 to 1.1) | 0.462 | |
Leg pain intensity during last week LN [(NRS 0–10) + 0.5]e b | Baseline | 145 | 161 | 0.9 (0.1) | 0.9 (0.1) | 0.1 (-0.4 to 0.5) | 0.805 | 0.1 (-0.4 to 0.6) | 0.708 |
Change 3 m | 91 | 105 | -0.2 (0.2) | 0.01 (0.2) | -0.2 (-0.8 to 0.4) | 0.407 | -0.2 (-0.8 to 0.4) | 0.395 | |
Change 12 m | 79 | 105 | 0.4 (0.2) | -0.2 (0.1) | -0.1 (-0.7 to 0.4) | 0.506 | -0.2 (-0.7 to 0.4) | 0.491 | |
ODI%b | Baseline | 145 | 161 | 23.5 (1.3) | 24.0 (1.2) | -0.5 (-4.0 to 3.1) | 0.795 | 0.2 (-3.4 to 3.7) | 0.925 |
Change 3 m | 91 | 105 | -5.1 (1.8) | -3.4 (1.7) | -1.7 (-7.6 to 4.1) | 0.501 | -1.7 (-7.6 to 4.1) | 0.511 | |
Change 12 m | 79 | 104 | -5.7 (2.4) | -4.1 (2.2) | -1.6 (-10.1 to 6.9) | 0.645 | -1.7 (-10.2 to 6.7) | 0.619 | |
EQ5D-3L indexdb | Baseline | 145 | 161 | 0.659 (0.023) | 0.664 (0.022) | -0.005 (-0.089 to 0.080) | 0.890 | < 0.001 (< 0.001 to 0.084) | 0.807 |
Change 12 m | 79 | 107 | 0.048 (0.029) | 0.053 (0.025) | 0.005 (-0.081 to 0.071) | 0.894 | -0.007 (-0.083 to 0.070) | 0.859 | |
Self-rated health EQ5D-VAS (0–100)b | Baseline | 144 | 159 | 68.2 (2.5) | 67.1 (2.4) | 1.1 (-7.3 to 9.4) | 0.771 | 0.5 (-7.9 to 8.8) | 0.899 |
Change 12 m | 75 | 103 | 5.4 (2.4) | 5.6 (2.1) | -0.1 (-6.5 to 6.2) | 0–970 | 0.03 (-6.4 to 6.4) | 0.992 | |
% (n) | % (n) | OR (95% CI) | OR (95% CI) | ||||||
LBP frequency (daily LBP yes/no)c | Baseline | 147 | 161 | 43.4 (63) | 50.9 (82) | 0.79 (0.57 to 1.09) | 0.143 | 0.80 (0.55 to 1.16); | 0.244 |
3 months | 38.7 (36) | 42.6 (46) | 0.94 (0.61 to 1.44) | 0.768 | 0.94 (0.50 to 1.49) | 0.792 | |||
12 months | 83 | 107 | 28.9 (24) | 32.7 (35) | 0.85 (0.48 to 1.51) | 0.586 | 0.84 (0.48 to 1.49) | 0.560 |
Secondary outcomes
Sensitivity analyses
First contacted professional | Physician (Intervention n = 84, control n = 51) | Physiotherapist (Intervention n = 67, control n = 114) | ||||
---|---|---|---|---|---|---|
Intervention | Control | Intervention | Control | |||
Imaging (yes/no)a | % (n) | % (n) | OR (95% CI); P value | % (n) | % (n) | OR (95% CI); P value |
Imaging 3 months | 7.3 (6) | 29.4 (15) | 0.15 (0.09–0.24); < 0.001 | 10.4 (7) | 11.4 (13) | 1.23 (0.30–5.61); 0.729 |
Imaging 12 months | 15.7 (13) | 42 (21) | 0.23 (0.16–0.33); < 0.001 | 17.9 (12) | 22.3 (25) | 0.91 (0.37–2.25); 0.842 |
Radiographs 3 months | 6.0 (5) | 19.6 (10) | 0.21 (0.19–0.23); < 0.001 | 4.5 (3) | 6.1 (7) | 0.88 (0.17–4.57); 0.882 |
Radiographs 12 months | 8.3 (7) | 23.5 (12) | 0.28 (0.25–0.31); < 0.001 | 9.0 (6) | 12.4 (14) | 0.79 (0.31–2.02); 0.616 |
Magnetic resonance imaging (MRI) 3 months | 3.6 (3) | 13.7 (7) | 0.17 (0.09–0.32); < 0.001 | 8.7 (6) | 5.3 (6) | 1.76 (0.57–5.48); 0.329 |
MRI 12 months | 9.5 (8) | 23.5 (12) | 0.33 (0.16–0.70); 0.004 | 15.9 (11) | 16.8 (19) | 0.91 (0.48–1.71); 0.760 |
PROMIS T-scoreb | Mean (SE) | Mean (SE) | Mean difference (CI); P value | Mean (SE) | Mean (SE) | Mean difference (CI); P value |
Baseline | 42.8 (1.0) | 42.2 (1.2) | 0.60 (-3.9 to 5.1); 0.713 | 45.9 (0.9) | 44.9 (0.8) | 1.1 (-1.4 to 3.5); 0.391 |
Change 3 m | 3.1 (1.1) | 1.3 (1.2) | 1.87 (-1.4 to 5.1); 0.254 | 2.2 (1.0) | 1.3 (0.8) | 0.9 (-1.7 to 3.6); 0.488 |
Change 12 m | 2.7 (1.7) | 1.3 (1.8) | 1.44 (-5.0 to 7.9); 0.591 | 1.7 (1.7) | 2.6 (1.3) | -0.9 (-8.7 to 6.8); 0.704 |
Sick leave daysc | Mean (SD) | Mean (SD) | RR (95% CI); P value | Mean (SD) | Mean (SD) | RR (95% CI); P value |
3 months | 4.9 (10.6) | 13.0 (23.2) | 0.35 (0.20–0.64); 0.001 | 1.4 (7.8) | 7.7 (21.6) | 0.24 (0.09–0.71); 0.010 |
12 months | 6.9 (16.7) | 16.0 (30.1) | 0.34 (0.23–0.51); < 0.001 | 4.5 (17.9) | 28.6 (78.6) | 0.17 (0.07–0.45); < 0.001 |
LBP-related health care appointmentsc | ||||||
Physician 3 months | 1.6 (1.5) | 2.2 (1.4) | 0.65 (0.55–0.75); < 0.001 | 0.3 (0.6) | 0.6 (1.2) | 0.39 (0.18–0.84); 0.017 |
Physician 12 months | 2.0 (2.2) | 3.0 (2.0) | 0.60 (0.49–0.72); < 0.001 | 0.9 (1.7) | 1.2 (2.3) | 0.72 (0.27–1.89); 0.501 |
Physiotherapist 3 months | 0.8 (1.3) | 0.6 (0.93) | 0.90 (0.59–1.58); 0.897 | 2.0 (1.2) | 1.6 (0.9) | 1.29 (1.16–1.43); < 0.001 |
Physiotherapist 12 months | 1.3 (2.6) | 1.2 (1.6) | 0.80 (0.47–1.37); 0.417 | 2.8 (2.1) | 2.4 (2.6) | 1.05 (1.02–1.09); < 0.001 |
Nurse 3 months | 0.3 (0.8) | 0.1 (0.4) | 1.22 (0.22–6.81); 0.823 | 0.1 (0.3) | 0.1 (0.3) | 1.39 (0.39–4.99); 0.617 |
Nurse 12 months | 0.8 (1.7) | 0.2 (0.7) | 1.73 (0.39–7.77); 0.474 | 0.3 (1.5) | 0.1 (0.3) | 5.19 (1.16–23.3); 0.031 |
Secondary health care 3 months | 0.37 (0.92) | 0.39 (0.67) | 0.79 (0.75–0.82); < 0.001 | 0.2 (0.9) | 0.3 (0.6) | 0.86 (0.30–2.50); 0.783 |
Secondary health care 12 months | 0.57 (1.17) | 0.53 (0.98) | 0.91 (0.88–0.95); < 0.001 | 0.6 (1.4) | 0.8 (2.1) | 0.84 (0.34–2.08); 0.699 |