Hi,

Some good references:

Meinhard KieserSpringer Series in Pharmaceutical Statistics Methods and Applications of Sample Size Calculation and Recalculation in Clinical Trials. Springer 2020

J. P. Verma, Priyam Verma Determining Sample Size and Power in Research Studies: A Manual for Researchers [1st ed.] Springer Singapore;Springer 2020

Campbell, Michael J.; Machin, David; Tan, Say Beng; Tan, Sze Huey

Sample size tables for clinical, laboratory and epidemiology studies [Fourth edition] 2018

Suggest you tell us what you want to do with the data and perhaps then someone can help you. David Booth

Dear Melese Tikusie

Read the following stuff as the authors provided the table about the population and sample size.

Krejcie, R. V., & Morgan, D. W. (1970). Determining sample size for research activities. Educational and Psychological Measurement, 30(3), 607–610. https://doi.org/10.1177/001316447003000308

Fleiss, J. L., Cohen, J., & Everitt, B. S. (1969). Large sample standard errors of kappa and weighted kappa, Psychological bulletin, Vol. 72 No. 5, pp. 323.

https://doi.org/10.1037/h0028106

Best of luck

Best regards

Dr. Muhammad Yousaf

Hello,

In order to compute sample size, I usually start defining the hypothesis, the primary goal and endpoint. Then, I try to look for similar previous studies to get a sense of the variability of our primary endpoint. From there on, there are many softwares out there for sample size calculation for different study designs. Each has its own advantages and disadvantages. Some of them are:

• Gpower.
• nQuery.
• PASS.
• www.sigdaan.com

Hope this helps!