Preliminary Study of Deep Learning based Speech Recognition Technique for Nursing Shift Handover Context

Abstract

Nursing shift handover involves conversations between nurses during duty handover. Handover contents have been recorded manually, and it is desirable to have an automatic speech recognition solution that transcribes audio speeches into texts. Even though there are excellent commercial Speech recognition solutions available, they are mainly designed for general contexts, which may not be most efficient for special contexts. This pilot study is to investigate speech recognition for the special contexts of nursing handover. To be more precise, we are to transcribe audios of 500 Chinese sentences conversed during nursing handover at the Taipei Hospital. A deep learning based network, Deep Speech 2 [1] working in conjunction with Beam Search Decoder with Language Model [2], is adopted for the intended automatic speech transcription. Special adaptation is considered for the audios is in Chinese: the recognition unit in DS2 is Chinese characters instead of letters as in English; the N-gram language model is also on Chinese characters rather than words as in English. Performance of the trained model has been conducted on two experiments: One is to transcribe audios made by people other than the people made the training audios. The other is to transcribe audios whose contents deviated from the recorded 500 sentences. For the former, the character error rate (CER) is 2.33%, as compared to that of 7.94% by Google Speech API [3]. For the latter, when the testing sentences are deviated from the training ones by 21% in word counts, the CER by the trained system is 13%. The results show promising foundation for more complicate sentences patterns.