Gpower: How can I estimate sample size for a EEG ERP study? It would help to know power and SD from previous studies but I did't find much. Thank you.

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Qin Xiang Ng

Hi,

Basically, there are two approaches to sample size calculation, precision-based (relevant if you are trying to estimate the proportion, mean difference etc) and power-based (relevant if you are trying to test a hypothesis; how small a difference is it important to detect and with what degree of certainty). See file attached for more details.

If you are unable to find previous studies, you can consider conducting a small pilot trial and use the estimates from that to calculate your ideal sample size.

Good luck!

Katharina Kühne

This is a brilliant idea, thank you!