OpenSpecimen allows you to add custom fields using the Custom Forms module. When creating dropdowns with a large set of values (more than 100 values), you need to first create the dropdown using 'Dropdown Manager' and then use it within the form. This page explains the steps to create such dropdowns.

Create the drop-down in a dropdown manager.
Go to Home→ Extras→ Dropdown Manager.
Click on the 'Add' Button and fill in the values.

Go to Home→ Extras→ Dropdown Manager→ Import → Dropdown value

Click on Download Template File

Fill the values in the 'Attribute' and 'Value' columns and save the file.

Note

In the 'Attribute' column, fill the 'Unique ID' column value as specified while creating the new dropdown above.
In the 'Value' field, fill the dropdown values.

Sample file

To make sure the values have been uploaded, go to Import → View Past Imports and check the import was successful.

Add Field to Form

Once the values are added in the dropdown manager, you can fetch these values by adding a 'Permissible Value' control.

Navigate to the “Forms“ module.
Click on the “+Create“ button.
Add “Permissible Value“ control field → Add Details like the label, attribute, and so on.

Add dropdown in 'Dropdown Manager'

Add values to the dropdown

Add Field to Form