Sample Size Estimation

Introduction: In general, sample size calculation is conducted through a pre-study power analysis. Its purpose is to select an appropriate sample size in achieving a desired power for correctly detection of a pre-specified clinical meaningful difference at a given level of significance. This study/tool will provide statistical procedures for determination of sample size required not only for testing equality, but also for testing non-inferiority/superiority, equivalence (similarity), some survival analysis and phase II clinical trials designs that are commonly employed at various phases of clinical development. As a handful tool, it is very useful for clinical scientists and biostatisticians in the pharmaceutical industry, regulatory agencies, academia, and other researchers.

This program helps users to determine sample sizes and confidence intervals for a wide range of statistical techniques including means, proportions, survival analysis, phase II clinical trials,epidemiological studies and some general cases).

DIRECTIONS:


Means

 

Proportions

Survival Analysis

Phase II Clinical Trials

Epidemiological Studies

Confidence Intervals

Others

1. Cohort Studies
      Based on relative risk precision
      Independent Cohort
      Paired Cohort

2. Case-Control Studies
      Based on odds ratio precision
      Unmatched Case-Control
      Matched Case-Control

3. Cross Sectional Studies
      One proportional x-Sectional
      Two proportional x-Sectional

4. Regression
      Simple Linear Regression
      Linear Regression comparing two slopes
      Simple Logistic Regression -- Binary Covariate
      Simple Logistic Regression -- Continuous Covariate