The EBM Toolbox

• About the Toolbox
• List of what's in the Toolbox
• Never mind all that, just take me to the evidence on: NNTs, SpPins and SnNouts, Likelihood Ratios, Prognosis, Pre-test Probabilities

We've used the Toolbox metaphor because you will find here an assortment of materials which are very useful for practitioners of EBM. Of course, this is not a completely exhaustive collection, and you may find gaps that need to be filled. So, not only can you retrieve information here, you can also comment and contribute. Use the comment icon (the speech bubble with an exclamation mark) to submit your own ideas. We'll study them and, if they work, we'll add them to the site, giving you the credit.

How to use this information

1. Look up the references!
2. This information is for integration with, not substitution for, your clinical expertise and personal knowledge, so don't blindly apply this stuff or blame bad outcomes on it.
3. Learn to recognise the icons and symbols used here.

Generic Resources:

• Asking Focused Clinical Questions.
• Educational Prescriptions, how to download one and what to do with it.
• Searching for the Best Evidence, some tips for MEDLINE users.
• Glossary of EBM Terms, giving brief definitions.
• Comparison of Study Designs, summarising the advantages and disadvantages of different types of study.
• All-Purpose 4-fold Table calculator, which (using Shockwave) allows you to do quick calculations.
• Levels of Evidence and Grades of Recommendation which can be applied to show the quality of evidence you have found.
• Quality Filters which we apply to the data appearing on these pages.
• Feedback page so you can comment on the material you see here and even add your own if you want.

Specific Tools and Data:

• Pre-Test Probabilities, with definition, how to calculate one, an example and some samples from real life.
• SpPins and SnNouts, with definition, how to calculate one, an example and a set of samples from real life.
• Likelihood Ratios, with definition, how to calculate one, an example, an interactive calculator and interactive nomogram for LRs (using Shockwave), and a set of samples from real life.
• NNTs (Numbers Needed to Treat), with definition, how to calculate one, an example and a set of sample s from real life.
• Confidence Intervals: download Dan Tandberg's Excel spreadsheet for calculating the CI around a difference between two proportions. (PC users: right-click on the link and choose Save Target from the menu if you want to save the file on your own machine)
• Prognosis, featuring an excellent synthesis of risk factors for cardiovascular events.