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Fig. 3 | Trials

Fig. 3

From: Effects of oral Nigella sativa oil on the expression levels and serum concentrations of adiponectin, PPAR-γ, and TNF-α in overweight and obese women: a study protocol for a crossover-designed, double-blind, placebo-controlled randomized clinical trial

Fig. 3

Formula for calculating sample size in crossover studies. δ is the clinically meaningful difference, μ2–μ1 is an expected true difference between the means, σ2 is the population variance, α is the significance level, and β is the power of the test

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