The Chilean Waiting List Corpus

In this work we describe the Waiting List Corpus consisting of de-identified referrals for several specialty consultations from the waiting list in Chilean public hospitals. A subset of 3000 referrals was manually annotated with 27892 entities, 1272 attributes, and 762 pairs of relations with clinical relevance. The corpus is 68 % medical and 32 % dental. A trained medical doctor or dentist annotated these referrals, and then together with other three researchers, consolidated each of the annotations. The annotated corpus has nested entities, with 35 % of entities embedded in other entities. We use this annotated corpus to obtain preliminary results for Named Entity Recognition (NER). The best results were achieved by using a biLSTM-CRF architecture using word embeddings trained over Spanish Wikipedia together with clinical embeddings computed by the group. NER models applied to this corpus can leverage statistics of diseases and pending procedures within this waiting list. This work constitutes the first annotated corpus using clinical narratives from Chile, and one of the few for the Spanish language. The annotated corpus, the clinical word embeddings, and the annotation guidelines are freely released to the research community. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.