| Study characteristics |
| Methods |
Study design: RCT
Setting: Spain, healthcare
Exercise groups: 1
Comparison groups: 1 |
| Participants |
Number of participants: 54 (E1 = 27, C1 = 27)
Chronic LBP duration: 14.5 months (moderate)
Neurological/radicular symptoms: No participants
Mean age (years): 39
Sex (female): 76% |
| Interventions |
Exercise Group 1 (E1): Pilates; type = Pilates; duration = 8 weeks; dose = low; design = partially individualised; delivery = not specified; additional intervention = none
Comparison Group 1 (C1): Other conservative treatment (education) |
| Outcomes |
Core outcomes reported: Pain (Visual Analogue Scale); function (Roland‐Morris Disability Questionnaire)
Follow‐up time periods available for syntheses: 8 weeks (short) |
| Notes |
Conflicts of interest: None to declare
Funding source: No funding received
Other: SDs imputed |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Random number generator in blocks of eight with no stratification |
| Allocation concealment (selection bias) |
Low risk |
Treatment allocation was concealed by using an independent third party to prepare randomised allocations, which were mailed to the study personnel. |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
1. Patients could not be blinded to allocation due to the nature of the treatments; 2. Unlikely that lack of patient blinding caused deviations from intended interventions; experimental group was structured and controlled by care providers, and control group was purposely broad. |
| Blinding of care provider (performance bias) |
Low risk |
1. Care providers could not be blinded to allocation due to the nature of the treatments; 2. Control group had minimal contact with care providers. |
| Blinding of outcome assessment (detection bias)
All outcomes |
High risk |
1. Outcome assessors for pain and function were patients themselves, who could not be blinded to allocation due to the nature of the treatments; 2. Pain and functional questionnaires are subjective, and responses could be altered by awareness of intervention; 3. Likely that lack of patient blinding introduced bias to outcome assessments, as the experimental group was clearly "better" than the control; study results for all outcome supported this. |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
1. No dropouts in this study |
| Participants analysed in group allocated (attrition bias) |
Low risk |
1. Appeared that all patients were analysed according to the allocation to which they were randomised |
| Selective reporting (reporting bias) |
Low risk |
1. No linked protocol or statistical analysis plan found: within this publication, all analysis and outcomes were fully reported. |
| Groups similar at baseline (selection bias) |
Low risk |
Both treatment groups were similar on all relevant baseline characteristics. |
| Co‐interventions avoided or similar (performance bias) |
Low risk |
"Participants were instructed to follow their normal schedule of medications and physical activity, without starting any new exercise programme or drug treatment throughout the course of the study". |
| Compliance acceptable in all groups (performance bias) |
High risk |
No report on attendance, despite the study claiming to have recorded this information |
| Timing of outcome assessment similar in all groups (detection bias) |
Low risk |
1. Outcome assessments were identical for all patients, regardless of treatment group; 2. Roland‐Morris Disability Questionnaire and Oswestry Disability Index (for function), and Visual Analogue Scale (for pain) are all well‐validated tools in the low back pain context. |
| Other bias |
Low risk |
Appeared free from other sources of bias |
