Koscielnny 1996.

Study characteristics
Methods	Study design: randomised, double‐blind, placebo‐controlled Method of randomisation: not stated Exclusions post randomisation: none Losses to follow‐up: 6/77 (8%)
Participants	Country: Germany Setting: university Number: 94 patients selected; 67 randomised Age: 'adults' Gender: not stated Inclusion criteria: CVI stage I to II Widmer Exclusion criteria: not stated
Interventions	Treatment: Buckwheat herb tea 3 × 1.8 g per day Control: placebo tea Duration: 84 days Follow‐up: 112 days
Outcomes	Primary Oedema, by reduction of leg volume Symptoms ‐ tenseness, heaviness, swelling, pain, paraesthesia, cramps, burning feet, restless legs, itching Secondary Side effects
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "After a placebo period of two weeks, patients were randomly assigned to active treatment or a placebo group" Comment: no information about methods of randomisation provided
Allocation concealment (selection bias)	Unclear risk	Comment: no information about methods of allocation concealment provided
Blinding (patients)	Low risk	Quote: "Placebo is with taste and appearance indistinguishable from the treatment" Comment: Identical placebo ensures double‐blinding
Blinding (study researchers)	Low risk	Quote: "Placebo is with taste and appearance indistinguishable from the treatment" Comment: Identical placebo ensures double‐blinding
Blinding (outcome assessment)	Low risk	Quote: "Placebo is with taste and appearance indistinguishable from the treatment" Comment: Identical placebo ensures double‐blinding
Incomplete outcome data	Low risk	Comment: number of participants in both placebo and treatment groups described, along with the most important participant characteristics, numbers of participants who dropped out prematurely, reasons for drop‐out, influence of drop‐outs and information on compliance
Selective reporting	Low risk	Comment: no published protocol identified, and no differences between outcomes reported in the methods section and those reported in the results section
Other bias	Low risk	Comment: none detected