Transforms for pharmacology and biochemistry

This page explains the special transforms for pharmacology and biochemistry. Other pages explain the built-in functions, and how to enter your own transforms.

On top of the transform dialog choose Pharmacology and biochemistry functions from the drop down and choose a transform by name.

Eadie-Hofstee, Hanes-Woolf, and Lineweaver-Burk transforms are used to plot enzyme-kinetic results. Scatchard transforms are used to display radioligand binding, and Hill plots are used to plot dose-response data.

Stop. Use these transforms only as a way to display data, not as a first step in analyzing data. You'll get better results by using nonlinear regression on the actual data.

Here is the mathematical definition of each transform:

Function	X becomes	Y becomes
Eadie-Hofstee	Y/X	No change
Hanes-Woolf	No change	X/Y
Hill	No change if you entered your data as log(conc.). Log10(X) if you entered your data as concentration.	log10(Y/(Ymax-Y)) (Prism prompts for Ymax)
Lineweaver-Burk	1/X	1/Y
Log-log	Log10(X)	Log10(Y)
Scatchard	Y	Y/X

Prism can also create Bland-Altman plots, which require a simple transform of the data. However, this is not done via a transform, but rather via a separate analysis.