Clinical Trial Size Calculator

Calculate Sample Size for Clinical Trial





Formula

The formula to calculate the Sample Size for a Clinical Trial is:

\[ n = \frac{Z^2 \cdot p \cdot (1 - p)}{E^2} \]

Where:

What is a Clinical Trial?

A clinical trial is a research study conducted to evaluate the effectiveness and safety of medical, surgical, or behavioral interventions. These trials are the primary way researchers find out if a new treatment, like a new drug or diet or medical device (for example, a pacemaker), is safe and effective in people. Often, a clinical trial is used to learn if a new treatment is more effective and/or has less harmful side effects than the standard treatment.

Example Calculation

Let's assume the following values:

Using the formula:

\[ n = \frac{1.96^2 \cdot 0.5 \cdot (1 - 0.5)}{0.05^2} \approx 384.16 \]

The Sample Size is approximately 384.16.