Sample size
inflammation, MCI
INFLAMMATION
The sample size was determined based on the number of participants required to detect significant changes in blood levels of inflammation and oxidation biomarkers between baseline visit (v0) and follow-up visits at 6 (v1) and 12 months (v2) in patients with MCI in the study group (treated with 240 mg of EGb 761 daily) compared to the control group. For this purpose, cystatin (mg/dL) was chosen as the reference variable since it has a known standard deviation. The average values and standard deviation of cystatin were obtained from an observational study in which the levels of cystatin in the blood of patients with MCI treated with EGb 761 at doses of 240 mg daily were determined (Gil P, 2018).Assuming that the study group’s cystatin level will be 0.97 mg/dL at the end of treatment and that the control group will maintain a cystatin level of 1.40 mg/dL, as well as a common standard deviation of 0.6, an alpha risk of 5%, a statistical power of 95%, and a drop-out rate of 20%, 50 participants per group would be required.