Best practice in statistics: Use the Welch t-test when testing the difference between two groups.

Clinical biochemists often wish to compare two groups of measurements. In order to do so, they must be familiar with Student's t-test. This article provides guidance for the use of the Welch t-test, with subtle but important differences and validity in a broader range of settings: advises the use of the Welch t-test rather than Student's t-test.