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Benchmark Dose Tools

Benchmark Dose Software (BMDS) Version 3 Support Articles

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Incompatibility between MScombo model and 64-bit Excel

Some users have experienced failure of the BMDS Multitumor (MScombo) model for runs of multiple datasets.

The failures seem to be related to an incompatibility between MScombo and 64-bit Excel.

We are hopeful that this will be fixed in BMDS 3.2.

In the meantime, if you need to perform perform analyses of multiple datasets with the Multitumor (MScombo) model , BMDS Announcement #71 includes several options for working around this issue.

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Reinstalling Excel May Solve Random Performance Issues

Some users have reported unusual error messages (such as “File not found: cmodels.dll”) or problems running analyses despite having a stable Microsoft Excel installation. In most cases, re-installing Excel solves these random problems.

For BMDS, we recommend a desktop version of Microsoft Excel for Windows with macros enabled (visit the Microsoft support site for information on enabling Excel macros). We recommend using the Office 365 or standalone Microsoft Office installation methods rather than installing via the Microsoft Store.

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Planned Features

The following features will be rolled out in future BMDS releases:
  • Analysis of two-dose datasets
  • Report parameter standard error (SE) values
  • Implement NCTR nested dichotomous model
  • Recompile models for improved speed (particularly for “Added Risk”)
  • Add Asymptotic Correlation Matrix of Parameter Estimates table to dichotomous output
  • Implement improvements to Results Workbook and Word Report feature
  • Implement confidence intervals for plotted group responses
  • Implement Cochran-Armitage trend test for dichotomous datasets
  • Implement data transformations on a column of data (for example, multiplying by a constant, returning the Log() base 10 of all values in a column, or converting standard errors to standard deviations, among other types of transformations)
  • Auto-update feature
  • Bayesian models for continuous response data
  • Bayesian model averaging for continuous response data
  • Sensitivity analysis for Bayesian priors (posterior distributions for alternative priors)
  • P-value (or equivalent) for Bayesian models
  • Covariate capability for all models
  • Risk-at-a-dose capability for all models
  • Model Averaging plots

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Specifying a Background Dose of Zero

This option is currently supported only for the frequentist dichotomous models.

If you specify the background dose to be zero , the resulting maximum-likelihood estimation (MLE) background parameters can sometimes still vary slightly above zero.

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If Checkboxes or Other Controls Display Oddly in 3.1

On first opening BMDS 3.1, you may see checkboxes or other onscreen artifacts offset from the main spreadsheet, as shown in the following screenshot.

On opening BMDS, checkboxes and other onscreen controls may display as offset and irregularTo correct this problem, select the "Display Settings" button at the bottom of the Excel window and then select "Optimize for Compatibility." You will need to restart Excel for the changes to take effect.

To correct display errors, select Display Settings and then Optimize for compatibility

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Specify Single Dataset/Option Combinations for Word Reports

For BMDS 3.1.1, we recommend that, when using the Word Report option, specify only single dataset/option combinations. Word Report generation improvements will be addressed in BMDS 3.2.

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Resolving Slow Performance

Some activities, such as generating the Results workbook, may slow BMDS performance of the performance of other applications on your computer.

Limiting the number of batch processes may help; try limiting the number of combinations of option sets, models, and datasets that BMDS is analyzing.

An all-purpose fix is to reboot the computer to clear the RAM and to run as few applications as possible while BMDS is processing.

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