Effect sizes of fixed and random effects model in Meta-Analysis

Over a few decades ago, meta-analysis has rapidly developed in various fields of studies to improve  the quality of previous research by quantitative review. Quantitative review assesses an overall  magnitude of the effect from multiple studies. Hence, the objective in this dissertation is to  determine the methods of finding effect sizes for different conditions in meta-analysis. Two key  findings of this study are as follows: Firstly, vote-counting method will be applied if the effect  size estimates are not available. Next, fixed effects and random effects methods will be used in  combining the effect size estimates when effect size estimates can be calculated. 55 Randomised  Controlled Trials (RCTs) on Tamoxifen treatment for early breast cancer  patients  are  observed   according to recurrences and mortality cases, respectively. The data is then analysed by using  the latest statistical software, Comprehensive Meta-Analysis (CMA) version 2.0. CMA is found to be  beneficial and interactive in the process of meta-analysis. The selection bias as well as the  publication bias should be avoided in order to produce better quality meta-analysis.