Question: what does mpi stand for in the medical field
[{'answer': 'master patient index', 'provenance': [{'wikipedia_id': '7043609', 'title': 'Enterprise master patient index', 'start_paragraph_id': 0, 'start_character': 11, 'end_paragraph_id': 0, 'end_character': 31, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '7043609', 'title': 'Enterprise master patient index', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 227, 'bleu_score': 0.9451524926983921, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7651845682934895407}, 'section': 'Section::::Abstract.'}]}]