Item Type Elements and Shortcodes

I want to use a shortcode to display a collection, sorted by an Item Type Element. My understanding is that it should read:

[items collection=124 sort=“Item Type Element,Start Date” order=a]

But it doesn’t seem to work. It will pull up the items, but not sort them correctly. I suspect that I have the element set named wrong, but what should I call it?

Thanks!

The set name for custom item type elements is “Item Type Metadata”

Thank you!!! That worked!