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Add dynamic randomization scheme

Randomization helps you avoid potential bias in the selection and allocation of subjects arising from the predictability of treatment assignments.

The dynamic randomization method adjusts the allocation probabilities based on the current distribution of participants by running the defined arm selector. The arm selector is a component of the randomization algorithm that determines the treatment arm to which a new participant is allocated based on certain predefined criteria or rules.

In IWRS, you can configure the arm selector by adding a randomization scheme.

To add a new dynamic randomization scheme

  1. In the IWRS application header, select the TREATMENT DESIGN tab.

  2. In the left pane of the page that opens, select Period.

  3. In the Period List table that appears, select the period within which you want to add a dynamic randomization scheme.

    Selecting period to configure
    Figure 1. Selecting period to configure

  4. In the period configurator tree, drill down and expand the cohort for which the dynamic randomization method is configured. From the expanded cohort menu, select Randomization List.

  5. On the Randomization List page that opens, from the workspace toolbar, select New Item add_new_icon.png.

    Selecting to add new randomization scheme
    Figure 2. Selecting to add new randomization scheme

  6. In the Add dialog that appears, complete the settings as explained in the following table.

    Adding new randomization scheme
    Figure 3. Adding new randomization scheme

    Tip

    In the following table, mandatory elements are marked with an asterisk (*).

    Element

    Details

    Randomization Name*

    Enter a unique name of the randomization scheme you create.

    Method*

    Select the method of subject randomization. Currently, only the Minimization method is supported by the system. According to this method, when a new subject is randomized, the system considers all the factors and allocates them to the treatment group (arm) that would minimize the imbalance.

    Type*

    Select how the arm selector for your randomization scheme is to be configured:

    • System Generate: select this option if the arm selector is to be configured by entering all the needed configuration parameters from scratch directly in the IWRS system.

    • Manual Upload: select this option if you want to configure the arm selector by uploading a configuration file from your computer and then mapping the fields in the file to the fields available in the IWRS system.

    Stratified by Sites

    Turn the toggle on so that the site is automatically used as the stratification factor.

    SAVE

    Select save_button_red.png to save the implemented changes.

    CANCEL

    Select cancel_button_white_blue.png to discard the changes without saving.

Once saved, a new randomization scheme is added and ready to be configured.

In this section:

A process during which subjects receive their random numbers and are assigned to different arms based on the randomization scheme.

A group of subjects formed as a result of randomization for blinding purposes that has its own schedule of visits and treatment plan according to a study protocol.