Probing Patient Messages Enhanced by Natural Language Processing: A Top-Down Message Corpus Analysis

Background. Patients increasingly use asynchronous communication platforms to converse with care teams. Natural language processing (NLP) to classify content and automate triage of these messages has great potential to enhance clinical efficiency. We characterize the contents of a corpus of portal messages generated by patients using NLP methods. We aim to demonstrate descriptive analyses of patient text that can contribute to the development of future sophisticated NLP applications. Methods. We collected approximately 3,000 portal messages from the cardiology, dermatology, and gastroenterology departments at Mayo Clinic. After labeling these messages as either Active Symptom, Logistical, Prescription, or Update, we used NER (named entity recognition) to identify medical concepts based on the UMLS library. We hierarchically analyzed the distribution of these messages in terms of departments, message types, medical concepts, and keywords therewithin. Results. Active Symptom and Logistical content types comprised approximately 67% of the message cohort. The "Findings" medical concept had the largest number of keywords across all groupings of content types and departments. "Anatomical Sites" and "Disorders" keywords were more prevalent in Active Symptom messages, while "Drugs" keywords were most prevalent in Prescription messages. Logistical messages tended to have the lower proportions of "Anatomical Sites,", "Disorders,", "Drugs,", and "Findings" keywords when compared to other message content types. Conclusions. This descriptive corpus analysis sheds light on the content and foci of portal messages. The insight into the content and differences among message themes can inform the development of more robust NLP models.