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ECOFFinder is a Microsoft Excel spreadsheet calculator that is freely available to the public. It is designed to estimate epidemiological cutoff values (ECVs, ECOFFs) for the minimal inhibitory concentrations or minimal effective concentrations of wild-type bacterial or fungal populations. It follows the methodology described in "Turnidge J, Kalhmeter G, Kronvall G. Statistical characterization of bacterial wild-type MIC value distributions and the determination of epidemiological cut-off values. Clin Microbiol Infect. 2006;12:418-425.” Instructions for use are provided on the Instructions sheet.

This version is an update to the previously released version. It overcomes the problem of requiring separate versions for PC and Mac. Includes a number of enhancements, including a “Results summaries” tab where some of the main results can be stored. Also included is “IMPORTANT ADVICE FOR USERS” which provides important caveats about the use of the product and the interpretation of results.

ECOFFinder XL 2010 v2.1

ECOFFinder for Excel Prior to 2010 (v1 for PC)

You will need to enable the Add-in “Solver.” Also, if you have enabled Solver and you get a runtime error the first time you use it, close and then re-open Excel to see if that fixes the problem.

For any issues or questions, contact John Turnidge (author): jturnidge@gmail.com.

If you are looking for RangeFinder, click here or contact standard@clsi.org.