I am working as a researcher in genetics field. I am proposing a study that I need to provide the appropriate sample size to get statistical approval.
The expected frequency of our event will be something between 8% and 12.8% When I used the following to calculate the sample size using this site, http://www.nss.gov.au/nss/home.nsf/pages/Sample+size+calculator, the confidence interval was 0.024, proportion was 0.104, confidence level 95%. The result is 622.
The issue now, i want to propose only 300. How i could argument this statistically?
NB. I have very basic stat knowledge. Can someone please explain in plain terms I could understand?