GraphPad Prism, available for both Windows and Mac computers, combines scientific graphing, comprehensive curve fitting (nonlinear regression), understandable statistics, and data organization.

GraphPad Prism was originally designed for experimental biologists in medical schools and drug companies, especially those in pharmacology and physiology. Prism is now used much more broadly by all kinds of biologists, as well as social and physical scientists. More than 200,000 scientists in over 110 countries rely on Prism to analyze, graph and present their scientific data. It is also widely used by undergraduate and graduate students.

Nonlinear regression
Nonlinear regression is an important tool in analyzing data, but is often more difficult than it needs to be. No other program simplifies curve fitting like Prism. In fact, you can usually fit curves in a single step. Just select an equation from the extensive list of commonly used equations (or enter your own equation) and Prism does the rest automatically — fits the curve, displays the results as a table, draws the curve on the graph, and interpolates unknown values.

Place data for multiple data sets side-by-side on an organized data table, and Prism can fit them all the data sets at once. You can fit the same model separately to each data set, use global nonlinear regression to share parameter values among data sets, or fit different models to different data sets.

Don’t be fooled by the simplicity. Prism also gives you many advanced fitting options. It can automatically interpolate unknown values from a standard curve (i.e., to analyze RIA data), compare the fits of two equations using an F test or Akaike’s Information Criterion (AIC), plot residuals, identify outliers, differentially weight data points, test residuals for normality, and much more.

Understandable statistics
While it won’t replace a heavy-duty statistics program, Prism lets you easily perform basic statistical tests commonly used by laboratory and clinical researchers. Prism offers t tests, nonparametric comparisons, one- and two-way ANOVA, analysis of contingency tables, and survival analysis. Analysis choices are presented in clear language that avoids unnecessary statistical jargon.

Unlike other programs, Prism provides understandable statistical help when you need it. Press “Learn” from any data analysis dialog and Prism’s online documentation will explain the principles of the analysis to help you make appropriate choices. Once you’ve made your choices, Prism presents the results on organized, easy-to-follow tables. The Prism documentation goes beyond anything you would expect. More than half of it is devoted to thorough explanations of basic statistics and nonlinear curve fitting, to teach you what you need to know to appropriately analyze your data.