Some Practical Guidelines for Effective Sample-Size Determination in Observational Studies

Wan Muhamad Amir Wan Ahmad (Department of Mathematics, Faculty of Science and Technology, Universiti Malaysia Terengganu (UMT).)
Wan Abdul Aziz Wan Mohd Amin (Department of Language and Communication, Universiti Malaysia Terengganu (UMT))
Nor Azlida Aleng (Department of Mathematics, Faculty of Science and Technology, Universiti Malaysia Terengganu (UMT).)
Norizan Mohamed (Department of Mathematics, Faculty of Science and Technology, Universiti Malaysia Terengganu (UMT).)

Aceh International Journal of Science and Technology
Vol 1, No 2 (2012): August 2012

Abstract- The purpose of this present study was to determine the right sample size in observational study which is focusing on medical or health sciences field. Sample size calculation is actually depends on the type of how the study is designed. For example different formulas are used to calculate the sample size in different type of the study. In this article, the formula of single proportion and two proportions is discussed and an example from medical research, which may contribute to the understanding of this problem, is presented.