Z-test : A Brief Overview Date: Sunday, January 09 @ 06:41:22 IST Topic: Biostatistics Print this page In some situations the sequence of steps used in t-test can be done using z-scores instead of t-scores. Then such a test is called z-test. Use: z-test is/can be used in place of t-test when • The population standard deviation is known which allows the standard error, rather than the estimated SE to be found • The sample is sufficiently large (n > 200) for the SD to provide a reliable estimate of SE. Funda: Although there a situations in which a t-test can be used but z-test cannot, there are no situations in which a z-test can be used but a t-test cannot. So t-tests are the most important and widely used of the two. Source: Page 79; RxPG Biostatistics Buster, Tyagi, Jaypee Publishers. This article comes from RxPG http://www.rxpgonline.com The Largest Community Website for Medical Students and Doctors The URL for this story is: http://www.rxpgonline.com/article1187.html