trial design, optimised.

KERUS™ Support

Learn more about our software, view online manuals, get the latest downloads, and more. Connect with other  users, or get support and professional advice from Exploristics.

Kerus Resources

Learn more about our software, view online manuals, get the latest downloads, and more. Connect with other  users, or get support and professional advice from Exploristics.

Please feel free to get in touch with your comments, questions or to inquire about our software we look forward to hearing from you.

Frequently asked questions

Can I design a trial to test a biomarker’s ability to discriminate between treatment responders and non-responders?

KERUS™ can evaluate designs for trials focusing on the utility of molecular markers (biomarkers) to predict patient response using Area Under the Curve of Receiver-Operator Characteristics (AUCROC) for continuous biomarker values or using sensitivity/specificity statistics for binomial values. In these trials, the investigator will have knowledge of the response of each subject before the trial begins, so a case-control design should be used. As with any KERUS™ design simulation multiple cohort sizes and subject allocation ratios can be entered into the design. Any relevant variable and correlation parameters should also be defined so that KERUS™ can generate a realistic approximation of the biomarker’s association with response. In the KERUS™ analysis tab, the user can select AUCROC, or sensitivity/specificity statistics from the drop-down menus depending on the biomarker distribution type. The user should define trial success criteria, or objectives, through the drop-down menus in the Analysis tab based on their desired trial specifications.  After data simulation KERUS™ summarises the probability of achieving each objective for each entered trial design possibility in simple barcharts or heatmaps to facilitate easy interpretation. Read more…

How can I vary the drop-out rate depending on the time interval from the start of the study?

In many cases, the rate of subject drop-out (censorship) from a trial is not completely random, but can instead vary with time. KERUS™ users may weight subject censorship rates to increase or decrease with time. In order to achieve this, the binomial censorship and Weibull/exponential time-to-event variables should be added as correlated variables within KERUS™. Changing a variable between independent and correlated is achieved through the “Correlated?” tick box within the Add Variable dialogue. Defining a relationship between these two variables will vary the censorship rates with time. A positive correlation coefficient will weight censorship to later time points. A negative correlation coefficient will weight censorship to earlier time points. Read more…

How do I save my simulated data to analyse in another program?

KERUS™ allows the user to view and save the simulated data underlying the trial analysis through the View buttons within the Analysis tab. The View buttons will only be available after the ‘Simulate and Evaluate’ process has been performed. KERUS™ users can use these buttons to select subsets of the simulated data based on simulation iteration and/or trial design scenario. After selecting the desired simulation/scenario subsets, clicking the ‘Preview Data’ button will open a new window containing the selected simulated datasets. The data can be saved as a comma separated value (.csv) file through the ‘Save’ button located in the lower left corner. Read more…

I only have medians and ranges, how do I define my variables?

KERUS™ simulates variables based on the assigned distributions and relationships to other variables. KERUS™ must be supplied with sufficient information on the variable distribution type and associated parameters for effective simulation. Medians and ranges do not supply enough information on the distribution and, therefore, cannot be used to define variables within KERUS™. It is advisable to return to the original data to determine the distribution type and appropriate parameters. Read more…

 How do I export the parameters of my trials?

KERUS™ users may want to create a record of trial simulation parameters, variables and relations, accessible from outside KERUS™, for future audit or distribution to other KERUS™ users. KERUS™ allows the user to create a Microsoft Excel Workbook (.xlsx) containing all the parameters, variables and relation information for each trial scenario through the ‘View Trial Setup’ menu option. If multiple trials have been added to a single session, information from all trials will be saved within a single Excel Workbook file. This file can will contain two worksheet tabs: ‘Data Summary’ where trial and defined variable parameters can be found, and ‘Correlations’ where defined variable relation coefficients can be found. Read more…