Pilot study [Power / Sample Size]
❝ What speaks against a pilot study?
Unfortunately, it's not a common practice in our country (Belarus). If not a pilot study what are other options? Sequential (if yes, how to implement it)? The usual 2X2 design with arbitrary, say a bit more than 30 subjects, sample size? Any other reasonable approaches?
Edit: Full quote removed. Please delete everything from the text of the original poster which is not necessary in understanding your answer; see also this post! [Ohlbe]