Thank you for your reply! I recently found an equation that defines the primary threshold of an F-test in terms of Cohen's d: F = d^2 * (n₁*n₂/(n₁+n₂). 

I was wondering if I could use a desired effect size to determine a primary threshold with this equation and then apply this threshold in NBS as an F-test. Is it OK?

Best regards,
Erfan