Read after write consistency (test refresh interval)

I have a refresh interval of 1 s. I want to confirm that this is actually happening. Is there a test to validate the item getting indexed is getting searchable in a second? If so, How do I do that? I am ingesting documents via _bulk. While this is helping, how could I send search requests to prove that the documents are retrieved within 1 s of getting indexed

Please share your insights!

You'd need to run a looping query against the index to check this, there's nothing native to the stack that can provide this guarantee.