All-Purpose 4-fold Table Analyser

The CATmaker's Scratching Post.

Type the appropriate numbers in the white boxes (you can TAB between boxes to save using the mouse); Click (or un-click) the sets of calculations you want to do (Rx for therapy, Dx for diagnosis and H for harm/aetiology); Click CALC; Click CLEAR to, er, clear the values and start again Please note that you will need the Shockwave plug-in to view this interactive image. If you do not have Shockwave installed, you will be presented with the opportunity to download it. We recommend you do so, as this adds functionality to your browser. Note that this image is 20K.

• Click here to find out about the full CATmaker,
• here to use a more extensive table for diagnosis, or
• here to see an interactive nomogram for post-test probabilities.

• You can even email us to let us know how it could be improved