| Study characteristics |
| Methods |
Study design: RCT
Setting: Denmark, healthcare
Exercise groups: 2
Comparison groups: 0 |
| Participants |
Number of participants: 350 (E1 = 175, E2 = 175)
Chronic LBP duration: 94.5 weeks (moderate)
Neurological/radicular symptoms: Some participants
Mean age (years): 38
Sex (female): 56% |
| Interventions |
Exercise Group 1 (E1): McKenzie treatment after individual assessment; type = McKenzie; duration = 12 weeks; dose = low; design = individualised; delivery = individual; additional intervention = advice/education
Exercise Group 2 (E2): General mobilising exercises, lumbar flexion/extension movement and stretching without directional preference; type = flexibility/mobilising & stretching; duration = 12 weeks; dose = low; design = individualised; delivery = individual; additional intervention = advice/education & manual therapy |
| Outcomes |
Core outcomes reported: Pain (Pain Rating Scale); function (Roland‐Morris Disability Questionnaire); work (return to work); HRQoL (36‐Item Short Form Survey); Global Perceived Health or Recovery (Global Perceived Health or Recovery (Global Perceived Effect scale))
Follow‐up time periods available for syntheses: 12 weeks (short); 20 weeks (moderate); 64 weeks (long) |
| Notes |
Conflicts of interest: Not reported
Funding source: Grant, Foundation, and Professional Organizational funds (sources not indicated)
Other: Sufficient data not available for inclusion in meta‐analyses |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomisation was carried out by a computer‐generated list of random numbers in blocks of 10 using sealed envelopes. |
| Allocation concealment (selection bias) |
Low risk |
A secretary who was not involved in the study prepared opaque, sequentially numbered envelopes indicating one of the two treatments. |
| Blinding of participants and personnel (performance bias)
All outcomes |
High risk |
Assumed not possible |
| Blinding of care provider (performance bias) |
High risk |
Blinding of the practitioners in one group to the treatment given in the other group was not possible. |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
Follow‐up assessment was carried out by a secretary blinded to treatment allocation at the end of treatment, after two months, and one‐year post‐treatment. |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
A statistically significant larger proportion of patients withdrew or was excluded during treatment in the manipulation group. |
| Participants analysed in group allocated (attrition bias) |
Low risk |
Intention‐to‐treat analysis was performed on all participants in the study. |
| Selective reporting (reporting bias) |
Low risk |
Support for judgement was not available. |
| Groups similar at baseline (selection bias) |
Low risk |
Baseline characteristics were similar for the two treatment groups except for the fact that significantly more patients were on sick leave. |
| Co‐interventions avoided or similar (performance bias) |
Low risk |
Patients were encouraged not to seek any other kind of treatment for the two months period of self‐administered exercises. |
| Compliance acceptable in all groups (performance bias) |
Unclear risk |
Not described |
| Timing of outcome assessment similar in all groups (detection bias) |
Low risk |
Support for judgement was not available. |
