Digital quantification has made it easier to increase experimental throughput and thus, produce large data sets. There are several programs on the market, such as Imaris®
Suite from Bitplane AG, that allow one to generate data from images. These programs can quantify various biological processes including protein colocalization, fluorescence intensity, and structural volume. However, it can be overwhelming to organize and interpret spreadsheets without having a good understanding of biostatistics and analysis software. It is also important to be able to graphically represent the data in order to portray the scientific significance of an experiment.
Prism from GraphPad has made it extremely easy to analyze data and graph experiments in a very professional and scientific manner. It incorporates biostatistics and scientific graphing in an all-inclusive program enabling one to pick the appropriate analytical tests and produce a variety of graphs. The best aspect of this program is that it provides step-by-step instructions on organizing, analyzing, and graphing data sets. Prior knowledge of statistics is not necessary, making it easier for one to concentrate on the data rather than trying to learn how to use the software.
The possibilities are endless in how GraphPad Prism can perform biostatistics. I have been able to analyze an extremely large data set within a matter of minutes. One study involved quantifying approximately 100 cells in five transgenic mice representing three different disease models. It was necessary to compare these transgenics with one another as well as with controls. The Spot Count module in Imaris® Suite from Bitplane AG enabled quantification of confocal images and produced spreadsheets of the cell counts. These statistics were saved from Imaris directly to Excel spreadsheets. I then imported this data to Prism by simply copying and pasting the variables of interest from Excel to defined columns in Prism.
Prism makes it easy to import the data and label the variables required for analysis. As you import the data and define your variables, Prism will automatically generate a bar graph with all of the appropriate labels and legends. The ‘Analyze’ button in the program provides various statistical tests including t tests, repeated measures tests, and analysis of variance (ANOVA). For this particular study, I used a one-way ANOVA. The best feature of the analysis is that it will automatically generate a post-analysis spreadsheet indicating the groups that are significantly different at your specified confidence level.
The graphs generated can easily be edited for an optimal visual representation of your experiment. GraphPad Prism allows you to effortlessly edit your graphs and you can make changes such as font size, font color, bar color, and axis labeling. You can also add text to the graph and create a figure that can be used for publication purposes. It is also easy to export the graphs as images in various formats (jpeg, tiff, etc.).
The company allows you to use their software for 30 days free of charge to help you decide whether the software is useful for your application. You can download the free-trial at their website (www.graphpad.com) and it can be used on either a PC or Macintosh platform. The nice thing about the trial version is that there is no limitation or restriction to the program. The website also gives you the option to download a comprehensive Help Guide that is almost like a ‘biostatistics for dummies’ manual. The company tries to provide you with all the information possible so that if any questions arise you will have the resources to find the answers. GraphPad Prism is so well designed, however, there is almost no need to look at the user’s manual.
Research Associate II
Buck Institute for Age Research
Morphology & Imaging Core