Coxhead 1981.

Methods	RCT; factorial design
Participants	Subjects: 334 patients with pain of sciatic distribution with or without LBP; 185 men and 149 women. Mean age 41.9, mean duration of symptoms 14.3 weeks. Exclusion criteria: specific LBP, patients undergone trunk, lower‐limb or spinal surgery within the previous three months and pregnant & postpartum women.
Interventions	Treatment intervention: 1) Fabric made lumbar support, 4 weeks (n=124). No data on number of hours / day. Control interventions: 2) No lumbar support (n=168).
Outcomes	Pain, overall improvement and turn to work / normal activities. No differences after 4 weeks, 4 months and 16 months.
Notes	334 patients entered the study, 12 were later found ineligible. Of these 322 patients, 292 were assessed at 4 weeks. At 4 months 250 patients and at 16 months 258 patients were assessed. No data available regarding compliance.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Low risk
Allocation concealment?	High risk	C ‐ Inadequate
Blinding? All outcomes ‐ patients?	High risk
Blinding? All outcomes ‐ outcome assessor?	High risk
Incomplete outcome data addressed? All outcomes ‐ drop‐outs?	High risk
Incomplete outcome data addressed? All outcomes ‐ ITT analysis?	Low risk
Similarity of baseline characteristics?	Unclear risk	Unclear from text
Co‐interventions avoided or similar?	High risk
Compliance acceptable?	High risk
Timing outcome assessments similar?	Low risk