Yozbatiran 2004.

Study characteristics
Methods	Study design: RCT Setting: Turkey, healthcare Exercise groups: 2 Comparison groups: 0
Participants	Number of participants: 30 (E1 = 15, E2 = 15) Chronic LBP duration: Not specified (not specified) Neurological/radicular symptoms: No participants Mean age (years): 39 Sex (female): 77%
Interventions	Exercise Group 1 (E1): Warm‐up, stretching, progressive exercises, light aerobics on land; type = mixed; duration = 4 weeks; dose = low; design = partially individualised; delivery = group; additional intervention = not specified Exercise Group 2 (E2): Warm‐up, stretching, progressive exercises, light aerobics in water; type = mixed; duration = 4 weeks; dose = low; design = partially individualised; delivery = group; additional intervention = not specified
Outcomes	Core outcomes reported: Pain (Visual Analogue Scale); function (Oswestry Disability Index) Follow‐up time periods available for syntheses: 4 weeks (short)
Notes	Conflicts of interest: Not reported Funding source: Not reported Other: None
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described
Allocation concealment (selection bias)	Unclear risk	Support for judgement was not available.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Support for judgement was not available.
Blinding of care provider (performance bias)	High risk	Support for judgement was not available.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Support for judgement was not available.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Support for judgement was not available.
Participants analysed in group allocated (attrition bias)	Low risk	Support for judgement was not available.
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)	Unclear risk	Support for judgement was not available.
Compliance acceptable in all groups (performance bias)	Low risk	Support for judgement was not available.
Timing of outcome assessment similar in all groups (detection bias)	Low risk	Support for judgement was not available.

For studies assessed using ROB 2 tool (indicated by numbering in the support for judgement column), the numbering indicates:

Blinding of participants: 1. Were participants blinded to the intervention?; 2. Did lack of patient blinding lead to deviations from the intended intervention due to the experimental context?; 3. Were these deviations balanced between groups (patient)?; 4. Were these deviations likely to have affected the outcome (patient)?

Blinding of care provider: 1. Were care providers blinded to the intervention?; 2. Did lack of care provider blinding lead to deviations from the intended intervention due to the experimental context?; 3. Were these deviations balanced between groups (provider)?; 4. Were these deviations likely to have affected the outcome (provider)?

Blinding of outcome assessment: 1. Were outcome assessors blinded to the intervention?; 2. Could the assessment have been altered by a lack of blinding (i.e. do the measures being assessed require judgement?); 3. Is it likely that the assessment of outcome was altered by a lack of blinding?

Incomplete outcome data: 1. Was the dropout rate described and acceptable? (please provide %, if available); 2. Is there evidence that the analysis was NOT biased by missing data?; 3. Could missingness in outcome depend on its true value?; 4. Do the missingness rates differ between groups?; 5. Is it likely that missingness in outcome depends on its true value?

Participants analysed in group allocated: 1. Was the intention to treat analysis included?; 2. Was it likely to have affected the result?

Selective reporting: 1. Was the study analysed and fully reported according to a pre‐specified plan?; 2. Was the outcome reported likely selected on the basis of the results it gave?; 3. Was the analytic method reported likely selected on the basis of the results it gave?

Timing of outcome assessment similar in all groups: 1. Were the outcome assessments similar between groups (timing, tools, scales, and thresholds,etc)?; 2. Were tools/scales used to measure the outcome(s) valid?

*Note that there are inconsistencies with some of our risk of bias judgements and reasons provided across studies. These inconsistencies have resulted from differing consensus decisions for sets of reviewers over time (assessments were conducted over 15 years) and some consistent differences between studies assessments of studies with the RoB 1 vs RoB 2 tools (i.e. different assessment criteria and introduced with the algorithm used to convert RoB 2 to RoB 1 for presentation here). The different judgements would not affect the certainty of evidence.

ANOVA: analysis of variance; HRQoL: health‐related quality of life; ITT: intention‐to‐treat; LBP: low back pain; RCT: randomized controlled trial; SD: standard deviation