Table 1.
Research questions.
| ID | RQa |
| RQ1 | What are the key properties of data used to train and evaluate machine learning models? |
| RQ2 | What types of NLPb tasks have been supported by machine learning? |
| RQ3 | How can NLP based on machine learning be applied in clinical practice? |
aRQ: research question.
bNLP: natural language processing.