| Study characteristics |
| Methods |
Study design: RCT
Setting: Japan, healthcare
Exercise groups: 1
Comparison groups: 1 |
| Participants |
Number of participants: 201 (E1 = 103, C1 = 98)
Chronic LBP duration: Not specified (not specified)
Neurological/radicular symptoms: No participants
Mean age (years): 42
Sex (female): 55% |
| Interventions |
Exercise Group 1 (E1): Trunk strengthening (trunk flexor and extension exercises), stretching (abdominal and back muscles, iliopsoas, gluteals and hamstrings), physician visits to ensure compliance; type = strengthening & stretching; duration = 8 weeks; dose = low; design = standardised; delivery = group; additional intervention = advice/education
Comparison Group 1 (C1): Other conservative treatment (anti‐inflammatory/analgesics) |
| Outcomes |
Core outcomes reported: Pain (Visual Analogue Scale); function (Roland‐Morris Disability Questionnaire)
Follow‐up time periods available for syntheses: 8 weeks (short); 26 weeks (moderate); 52 weeks (long) |
| Notes |
Conflicts of interest: None to declare
Funding source: No funding received
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 |
The allocation sequence was produced by a computer‐generated, permuted‐block randomisation with a block size of four. |
| Allocation concealment (selection bias) |
Unclear risk |
The office managed the patient registration including confirmation of the eligibility criteria, randomisation to an allocated treatment, and data management. |
| Blinding of participants and personnel (performance bias)
All outcomes |
High risk |
Not described |
| Blinding of care provider (performance bias) |
High risk |
Not described |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
The outcome measures were conducted in a blinded fashion by a person who was not involved in this trial. |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
Among all eligible participants, two in exercise and six in Non‐steroidal anti‐inflammatory drugs dropped out during the follow‐up period. |
| Participants analysed in group allocated (attrition bias) |
Unclear risk |
Analysis was by intention‐to‐treat. |
| Selective reporting (reporting bias) |
Low risk |
Support for judgement was not available. |
| Groups similar at baseline (selection bias) |
Low risk |
There were no statistically significant differences in age, gender, body height, body weight, body‐mass index, Visual Analogue Scale, Roland‐Morris Disability Questionnaire, Japan Low back pain Evaluation Questionnaire, and finger‐floor distance. |
| Co‐interventions avoided or similar (performance bias) |
Low risk |
A run‐in period of two weeks was designed to ensure the stability of patient low back pain before starting the intervention. |
| Compliance acceptable in all groups (performance bias) |
Low risk |
The follow‐up system for participants was also distinctive compared with other studies with a treatment diary used to record daily exercise and medication. |
| Timing of outcome assessment similar in all groups (detection bias) |
Low risk |
Support for judgement was not available. |
