| Study characteristics |
| Methods |
Study design: RCT (NCT02132910)
Setting: USA, healthcare
Exercise groups: 1
Comparison groups: 1 |
| Participants |
Number of participants: 68 (E1 = 34, C1 = 34)
Chronic LBP duration: Not specified (not specified)
Neurological/radicular symptoms: Some participants
Mean age (years): 44
Sex (female): 63% |
| Interventions |
Exercise Group 1 (E1): Yoga with a special focus on major muscles affected by chronic LBP (back and core); type = yoga; duration = 8 weeks; dose = low; design = partially individualised; delivery = individual; additional intervention = other
Comparison Group 1 (C1): Usual care/no treatment (usual care based on participants provider: medication, physiotherapy, chiropractic care, massage, supplements, etc.) |
| Outcomes |
Core outcomes reported: Pain (Numerical Rating Scale); function (Roland‐Morris Disability Questionnaire); HRQoL (Patient‐Reported Outcomes Measurement Information System‐29 Symptom Burden)
Follow‐up time periods available for syntheses: 13 weeks (short); 26 weeks (moderate) |
| Notes |
Conflicts of interest: None to declare
Funding source: U.S. Department of the Army, Telemedicine and Advanced Technology Research Center; U.S. Army Medical and Materiel Command; Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. under Cooperative Agreement (W81XWH‐11‐2‐0201)
Other: Information modified for author contact |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
A computerised random number generator produced the randomisation table. |
| Allocation concealment (selection bias) |
Low risk |
Participants opened pre‐sealed envelopes labelled with the sequential enrolment number containing group assignment to conceal treatment allocation. |
| 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 the intended interventions because patients had little control over intervention delivery |
| 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. Unlikely for regular care providers to recommend or conduct yoga type treatment in a clinical setting; participants were randomised to yoga instructors. |
| Blinding of outcome assessment (detection bias)
All outcomes |
High risk |
1. Outcome assessors for pain and function were the patients themselves, who could not be blinded due to the nature of the treatments; 2. Pain and functional questionnaires are subjective, and responses could be altered by awareness of intervention; 3. Control was care‐as‐usual whereas the experimental group received a somewhat "trendy" intervention, which increased risk of bias; follow‐up was 4 weeks after intervention, 3 months after baseline, potentially lowering risk of bias. |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
1. Follow‐up data was available for all but 6 of 68 participants at the 3‐month follow‐up, 9%. |
| Participants analysed in group allocated (attrition bias) |
Low risk |
1. Intention‐to‐treat analysis was used. |
| Selective reporting (reporting bias) |
Low risk |
1. Study was analysed and reported according to registered protocol (NCT02132910), though a few more outcomes were in the article than the protocol (Physical Functioning and Symptom Burden). |
| Groups similar at baseline (selection bias) |
High risk |
Several characteristics were collected; only statistical test results were reported; data were not presented for interpretation. |
| Co‐interventions avoided or similar (performance bias) |
High risk |
Control group (treatment‐as‐usual) purposely allowed patients to use any medications, physiotherapy or other therapy that their care provider felt was necessary. |
| Compliance acceptable in all groups (performance bias) |
Low risk |
Compliance in treatment group was 82% (334 estimated attended sessions out of 408 maximum possible for 34 yoga group members); assumed 100% compliance for treatment‐as‐usual |
| 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 (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 |
