Suggested answer to exercise: Fisher's exact test?, 1

Question 1: Why is Fisher’s exact test wrong here? What assumption is violated?

Suggested Answer

The subjects in the table are not independent. The authors have completely ignored the fact that the 105 subjects classified by clinic measurements are the same as the 105 classified by ambulatory measurements. They count every subject twice and ignore the fact that they are the same subjects.

Fisher's exact test requires the observations to be independent.

Back to Exercise: Fisher's exact test?.

To Clinical Biostatistics index.

To Martin Bland's M.Sc. index.

To Martin Bland's home page.

This page maintained by Martin Bland.
Last updated: 31 July, 2006.

Back to top.