Alexander 1995.

Methods	RCT
Participants	Subjects: 60 health care workers; 48 women and 12 men. Mean age 37 years. Exclusion criteria: subjects who have had back surgery, current workers' compensation claims, cardiovascular problems or were pregnant. Authors did not report whether workers with LBP or a past history of LBP were included in the study.
Interventions	Preventive intervention: 1) Back belt group (n=30). Belt use at work for 3 months. Control intervention: 2) No intervention (n=30)
Outcomes	Perception of physical pain and work related back injuries. No significant differences after 3 months.
Notes	The most common complaints: belt rode up, changed position and increased perspiration. No data available regarding compliance.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Unclear risk	Unclear from text
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?	Low risk
Incomplete outcome data addressed? All outcomes ‐ ITT analysis?	Low risk
Similarity of baseline characteristics?	Low risk
Co‐interventions avoided or similar?	High risk
Compliance acceptable?	Unclear risk	No data available regarding compliance.
Timing outcome assessments similar?	Low risk