Friederich 1978.

Methods	Study design: crossover, randomised, double‐blind. Method of randomisation: not reported. Exclusion post randomisation: not reported. Losses to follow up: 23. Quality score = 4.
Participants	Country: Germany. Setting: hospital. No: 118 entered, 23 drop outs. Age: (mean) 48 and 47 years in men and women, respectively. Sex: males 11; females 107. Inclusion criteria: oedema, leg pain, pruritus, feeling of tenseness and fatigue. Exclusion criteria: not reported.
Interventions	Treatment: 1 capsule HCSE (standardised to 50 mg escin) twice daily. Control: placebo. Duration: 20 days.
Outcomes	Primary: (not explicitly defined) symptoms 1) leg pain 2) oedema 3) pruritus Secondary: (not explicitly defined) patients' impression of effectiveness.
Notes	Standardised mean difference (95% CI): Primary: 1), 2), 3) Not enough data provided for effect size calculation. Secondary: Not enough data provided for effect size calculation.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	Allocation concealment not reported
Blinding (performance bias and detection bias) All outcomes	Low risk	Treatment and placebo capsules were identical in terms of outer appearance
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	It is unclear how incomplete outcome data were addressed
Selective reporting (reporting bias)	Low risk	No evidence of selective reporting
Other bias	Unclear risk	No evidence of further biases