Setting a RadioItem created with ItemFactory

["Jeffrey Ratcliffe" <jeffrey ratcliffe gmail com>]

I have a group of RadioItems created with ItemFactory:

  { path        => '/_Frontend'),
    item_type   => '<Branch>' },
  { path        => '/_Frontend/scan_image',
    item_type   => '<RadioItem>',
    callback    => \&change_frontend,
    callback_action => 1 },
  { path        => '/_Frontend/scan_adf',
    item_type   => '/Frontend/scanimage',
    callback    => \&change_frontend,
    callback_action => 2 },

The callbacks work fine, but how can I set one of the items to be active?

Thanks for any help,

Jeff