Dramatic monologues, as they must create a character, necessarily create a persona; however, as a poem using a persona need not tell a reader anything about the situation of the speaker, the narrative, or the person that the poem is spoken to, a persona-poem need not be a dramatic monologue.
Some critics prefer to treat every 'I' as a persona. The biographical truth (or not) of, say, George Szirtes' 'Preston North End', would be considered irrelevant. Others allow a belief in poetry as personal testimony, which Samuel Menashe insists on in his introduction to 'Self-Employed'.
