> For the complete documentation index, see [llms.txt](https://docs.predicteasy.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.predicteasy.com/statistical-test/t-test.md).
# T-Test
**Use:** To **compare** **means of two groups** to determine if they are significantly different. To check if there is a statistically significant difference between the means of two groups. It's commonly used when you have a small sample size and want to understand if the means of two populations are significantly different.
**Example:** A pharmaceutical company wants to test if a new drug is more effective than a placebo in reducing blood pressure. They compare the average blood pressure measurements before and after treatment for both groups.
{% hint style="info" %}
**Column Requirement:** Continuous data is required for two independent groups.
{% endhint %}
**Steps:**
1. Select two continuous columns, each representing a group (e.g., blood pressure before and after treatment).
2. Ensure that the data distribution is approximately normal or at least not highly skewed.
3. Perform the t-test after selecting the columns using the Test button.
4. Interpret the results and draw conclusions accordingly.
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