Table S4.

Power analysis

Measurement	Reduction with stockings (n=17)	Effect size dz, (mean/SD)	n needed
			Power =0.8	Power =0.9
NVPQOL	10.18±19.41	0.52	31	41
CIVIQ	3.24±6.07	0.53	30	39
Dizziness	3.47±4.64	0.75	17	21
PUQE	0.33±1.05	0.33	91	112

Notes: Power analysis with G*Power version 3.1.7 based on an unpublished crossover pilot study. For NVPQOL and CIVIQ the numbers needed were 31 and 30 patients, respectively, with a power of 80%, and 41 and 39 patients with a power of 90%. As estimations were based on a small sample, the number of enrolled subjects was increased to 60.

Abbreviations: CIVIQ, Chronic Venous Disease Quality of Life questionnaire; d_z, Cohen’s d_z (effect size indicator for paired Student’s t-tests); n, number of patients; NVPQOL, Nausea and Vomiting in Pregnancy Quality of Life questionnaire; PUQE, Pregnancy-Unique Quantification of Emesis and Nausea; SD, standard deviation.