Aceso-DSAL: Discovering Clinical Evidences from Medical Literature Based on Distant Supervision and Active Learning.

Automatic extraction of valuable, structured evidence from the exponentially growing clinical trial literature can help physicians practice evidence-based medicine quickly and accurately. However, current research on evidence extraction has been limited by the lack of generalization ability on various clinical topics and the high cost of manual annotation. In this work, we address these challenges by constructing a PICO-based evidence dataset PICO-DS, covering five clinical topics. This dataset was automatically labeled by a distant supervision based on our proposed textual similarity algorithm called ROUGE-Hybrid. We then present an Aceso-DSAL model, an extension of our previous supervised evidence extraction model - Aceso. In Aceso-DSAL, distantly-labelled and multi-topic PICO-DS was exploited as training corpus, which greatly enhances the generalization of the extraction model. To mitigate the influence of noise unavoidably-introduced in distant supervision, we employ TextCNN and MW-Net models and a paradigm of active learning to weigh the value of each sample. We evaluate the effectiveness of our model on the PICO-DS dataset and find that it outperforms state-of-the-art studies in identifying evidential sentences.