Math Geek.... Power Analysis and Sample size

[mikedatiger]

Originally Posted by SaltERedneck

Anyone know about sample size and power analysis. I am writing a research paper and need to get a power analysis of 0.80. I would like my sample size to be large enough to yield this data. Would a sample size of n = 50 (group 1 = 25, group 2 = 25) provide this? This study will be reviewed by the IRB committee here in LC for approval. Realistically a sample size of 50 is unlikely in the sample i am researching (SQ insulin vs. IV insulin in the management of uncomplicated diabetic ketoacidosis) because this would require a year or so of data collection. Or if anyone can find a website that does the calculation I would be grateful.

Group 1 = IV insulin
Group 2 = SQ insulin

T test would be the given formula.

I'm no expert on this aspect but I believe you are going to need a rough estimate of the pop mean and std. deviation to test your sample size. You could play around with those inputs to back into your n.

You should be able to find a program online that you can trial to help you out. Don't know if Minitab can be used for this specific analysis but i have downloaded a trial in the past.