The first is the R code for the equipercentile equating algorithm that was used to estimate the equivalent score. This is what was used in both the Roalf et al., Alz & Dementia (2013) paper and the van Steenoven Movement Disorders (2014) paper. This will give you some idea on what we did to convert the scores when we had known MoCA and MMSE scores from the same individuals. I don't think that this is practical for your current effort, but it could be someday. 

The second R code (an associated tables) is simply the implementation of each of the conversion tables in the two papers cited above. This script will enable to you convert MMSE to MoCA or MoCA to MMSE scores (all at the same time). Given that the conversion is slightly different for AD and PD, we force this conversion to be based upon either the AD or PD sample. 

This code includes comments/instructions, which are provided as comments in the code. Basically, all you need to do is provide 3 columns: MMSE, MoCA and dx (diagnosis) in CSV format.  Your file can include as many other columns as you wish, but these three columns must be present. There is an example data file called "Test.csv" included in the attached .zip file. You will also need to update the file paths in the R code to reflect where you save your data and the included lookup tables. 

MMSE=MMSE score
MoCA= MoCA score
dx=AD, PD, Other. Note: These are the ONLY three options than can be used. 'Other' is anyone who is not AD or PD, including Healthy individuals. All the 'diagnosis' label really does is determine which look-up table to use (AD or PD version). The default for the 'Other' group is to use the AD look-up b/c a healthy sample was included in the original estimation and leads to more precise conversion estimates. If you are only using this code to convert for a sample of PD just make sure everyone has a PD label in the dx column. 

David R. Roalf, Ph.D.  Research Assistant Professor University of Pennsylvania Perelman School of Medicine  Department of Psychiatry Neuropsychiatry Section  3400 Spruce St,  10 Gates  Philadelphia, PA 19104  Phone: 215-615-4116  Fax: 215-662-7903  roalf@upenn.edu  www.davidroalf.com

