These computer programs for PCs accompany the paper: Crawford, J. R., Garthwaite, P. H., and Ryan, K. (2011). Comparing a single case to a control sample: Testing for neuropsychological deficits and dissociations in the presence of covariates. Cortex, 47, 1166-1178. (pdf)
The programs allow researchers to test for deficits (BTD_Cov.exe & BTD_Cov_Raw.exe) or dissociations (BSDT_Cov.exe & BSDT_Cov_Raw.exe) in the single case allowing for the effects of covariates. They are designed for use in the case-controls design; i.e., when inferences concerning a case are made by comparing the score(s) of the case to the scores obtained by a control sample.
The covariate methods provide the same full range of results provided by our earlier methods. That is they provide: (a) a significance test (i.e. tests whether we can reject the null hypothesis that the case's score, or score difference, is an observation from the scores, or score differences, in the control population); (b) point and interval estimate of the abnormality of the case's score, or score difference; and (c) point and interval estimates of the effect size for the difference between case and controls
The methods have a wide range of potential applications, e.g., they can provide a means of increasing the statistical power to detect deficits or dissociations, or can be used to test whether differences between a case and controls survive partialling out the effects of potential confounding variables.
Two of the programs (BTD_Cov.exe & BSDT_Cov.exe) take SUMMARY data for the control sample as input (means, SDs, and correlation matrix). The alternative versions of these programs (BTD_Cov_Raw.exe & BSDT_Cov_Raw.exe) take RAW data for the controls as input (i.e., the program computes the means, SDs, and correlation matrix from the raw control data prior to running the tests)
To download BTD_Cov.exe click here and save to disk (once downloaded click on the program icon to run) To download BTD_Cov_Raw.exe click here and save to disk (once downloaded click on the program icon to run) To download BSDT_Cov.exe click here and save to disk (once downloaded click on the program icon to run) To download BSDT_Cov_Raw.exe click here and save to disk (once downloaded click on the program icon to run) Two further programs that DO NOT allow for the effects of covariates are also available. These are upgraded versions of earlier programs (DiffBayes_ES.exe and DissocsBayes_ES.exe). The updated versions (DiffBayes_ES_CP.exe and DissocsBayes_ES_CP.exe) allow use of a calibrated prior (hence the CP suffix). DiffBayes_ES_CP.exe performs the Bayesian Standardized Difference Test (BSDT) when the analysis does not include covariates. DissocsBayes_ES_CP.exe applies Crawford & Garthwaite's (2007) criteria for classical and strong dissocations and also uses the BSDT and hence was also upgraded to allow use of a calibrated prior. We recommend use of the calibrated prior over the "standard theory" prior used in the earlier versions of these programs (the new programs still offer the standard theory prior as an option but the default is to use the calibrated prior). To download DiffBayes_ES_CP.exe click here and save to disk (once downloaded click on the program icon to run) To download DissocsBayes_ES_CP.exe click here and save to disk (once downloaded click on the program icon to run)Click here to download a zip file containing ALL SIX programs (once downloaded unzip the files and click on the icons to run)
Your web browser is most probably configured to recognise that the files are executable. If you have any problems (i.e. the browser treats them as text files), hold down the shift key when clicking. If your network does not allow downloads of executables then downloading the zip file is a solution.
The author of this software (John R Crawford) and the University of Aberdeen make no representations about the suitability of the software or about any content or information made accessible by the software, for any purpose.
The software is provided 'as is' without express or implied warranties, including warranties of merchantability and fitness for a particular purpose or noninfringement.
The software is provided gratuitously and, accordingly, the author shall not be liable under any theory or any damages suffered by you or any user of the software.
If there are any problems please e-mail me at j.crawford@abdn.ac.uk. Further contact details are available in the footer of this page.
