Recognizing Disjoint Clinical Concepts in Clinical Text Using Machine Learning-based Methods

With rapid growth of medical informatics technology, a large number of electronic health records (EHRs) have been available in recent years, including a huge mass of data, such as clinical narratives. They have been being used not only to support computerized clinical systems (e.g., computerized clinical decision support systems [1][2]), but also to help the development of clinical and translational research [3]. One of the challenges to use them is that much information is embedded in clinical notes, but cannot be directly accessible for computerized clinical systems which rely on structured information. Therefore, natural language processing (NLP) technologies, which can extract structured information from narrative text, have received great attention in medical domain [4], and many clinical NLP systems have been developed for different applications [5]. Clinical concept recognition (CCR) as a fundamental task of clinical NLP has also attracted great attention, and a large number of systems have been developed to recognize clinical concepts from various types of clinical notes in last two decades.