| Study characteristics |
| Methods |
Study design: RCT
Setting: Denmark, healthcare
Exercise groups: 2
Comparison groups: 0 |
| Participants |
Number of participants: 260 (E1 = 128, E2 = 132)
Chronic LBP duration: 54 weeks (moderate)
Neurological/radicular symptoms: No participants
Mean age (years): 35
Sex (female): 46% |
| Interventions |
Exercise Group 1 (E1): Strengthening training: stationary bike; intensive dynamic back strengthening in flexion and extension; type = core strengthening & aerobic; duration = 8 weeks; dose = low; design = partially individualised; delivery = group; additional intervention = none
Exercise Group 2 (E2): McKenzie therapy; type = Mckenzie; duration = 8 weeks; dose = low; design = individualised; delivery = individual; additional intervention = none |
| Outcomes |
Core outcomes reported: Pain (Visual Analogue Scale); function (Low Back Pain Rating Scale (Manniche)); work (self‐reported sick‐leave); Global Perceived Health or Recovery (Global Perceived Health or Recovery (global change in back‐related quality of life (5‐point))
Follow‐up time periods available for syntheses: 8 weeks (short); 35 weeks (moderate) |
| Notes |
Conflicts of interest: None to declare
Funding source: Foundation funds (source not indicated)
Other: None |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Support for judgement was not available. |
| Allocation concealment (selection bias) |
Low risk |
Approximately equal number of subjects in each group preferring the opposite treatment |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
Author contact: changed from not satisfied ‐ an equal number of subjects preferred other treatment |
| Blinding of care provider (performance bias) |
Low risk |
No, but they thought their treatment was the superior. |
| Blinding of outcome assessment (detection bias)
All outcomes |
High risk |
Self‐report |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
Sixty‐six per cent follow‐up |
| Participants analysed in group allocated (attrition bias) |
High risk |
Called it intention to treat, but did not include all patients randomised; third reviewer used for consensus |
| Selective reporting (reporting bias) |
Low risk |
Support for judgement was not available. |
| Groups similar at baseline (selection bias) |
Low risk |
Support for judgement was not available. |
| Co‐interventions avoided or similar (performance bias) |
Low risk |
General practitioner comparable; 'patients were encouraged not to seek any other'. |
| Compliance acceptable in all groups (performance bias) |
Low risk |
Author contact: changed from unclear ‐ stated they assessed compliance at > 70%; all compliant |
| Timing of outcome assessment similar in all groups (detection bias) |
Low risk |
Support for judgement was not available. |
