29. The system of claim 20 , further comprising a content-based model configured to detect whether an input text is responsive to a prompt.
29. The system of claim 20 , further comprising a content-based model configured to detect whether an input text is responsive to a prompt. 30. The method of claim 29 , wherein the content-based model is configured to: assign an input text to either one of one or more past prompts or to one of one or more current prompts; and if the input text is assigned to a past prompt, flag the input text for manual checking as possibly not responsive to the one or more current prompts.