Katz 1990.

Methods	Randomised controlled trial comparing bed rest and immersion in water for treating leg oedema in pregnancy.
Participants	Inclusion criteria: healthy pregnant women aged 26‐35 with singleton pregnancies between 34‐38 weeks' gestation. Total number of recruited participants was not mentioned in the paper. The authors stated that 11 women completed the study, of whom 6 were primigravida, numbers not split per randomised group. Exclusion criteria: none stated.
Interventions	Group 1: lateral supine bed rest at room temperature. Group 2: sitting in a bathtub of waist‐deep water at 32 ± 0.5 C with leg horizontal. Group3: sitting immersed in shoulder‐deep water at 32 ± 0.5 C with leg extended downward.
Outcomes	Outcomes reported: maternal heart rate, mean arterial pressure, urine output, haemoglobin, haematocrit, plasma volume, sodium clearance and adverse events. Infant outcomes: live birth, gestation at birth. Although, data not split per randomised group.
Notes	The authors stated that 50 minutes of shoulder immersion in water resulted in more diuresis and mean arterial blood pressure compared to bed rest. It was not possible to trace the authors. "All pregnancies ended with deliveries of infants between 38‐41 weeks gestation". "No women developed complications after the study was finished". Sample size: 11 women, numbers not split per randomised group. Country: North Carolina, USA. Study years: not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Women were 'assigned randomly', sequence generation not described.
Allocation concealment (selection bias)	Unclear risk	Allocation concealment not described.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Blinding not possible due to the nature of the intervention.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Blinding of outcomes assessors not described, but staff would have been aware of group assignment due to the nature of the intervention.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Total number of recruited participants was not mentioned in the paper. The authors stated that 11 women completed the study.
Selective reporting (reporting bias)	Low risk	Selective reporting not apparent.
Other bias	Low risk	None noted.