在現今醫療體系中，急診常常被認為是最有時效性的就醫途徑，然而為了能妥善的分配醫療資源，台灣急診醫學會和中華民國急重症護理學會參照加拿大檢傷分類系統架構制訂了台灣急診檢傷與急迫度分級量表(Taiwan Triage and Acuity Scale, TTAS)，其規範了台灣醫療檢傷系統的分類標準，而此系統在評估急診病患疾病的嚴重程度方面發揮了重要的功用。TTAS使用數字評分量表(Numerical Rating Scale, NRS)來評量病患自述疼痛程度作為其中主要調節檢傷的因子之一，然而對於無法清楚表達疼痛的病患，檢傷護士或其病患家屬將依照其個人主觀自行判斷，而這些因素將造成檢傷分類系統一致性及有效性的偏差。本論文與林口長庚醫院急診醫師合作，藉由提取病患臉部表情及聲音特徵的多模態行為訊號，人們在表達內在感受時，會經由外在的行為表現出來，而我們對這些外顯行為分別利用迴旋積類神經網路(Convolution Neural Network)和長短期記憶網路(Long Short-Term Memory)演算法的機器學習模型來進行建模，以達到自動化評估病患疼痛程度。由實驗結果顯示在二類及三類辨識疼痛程度的結果中，分別達到了77.1%和55.7%的準確率，而在實驗分析中我們也發現病患臉部表情和聲音特徵與其疼痛程度有顯著關係。透過本論文的實驗結果均呈現經由量化、分析病患外顯行為來達到自動化疼痛程度評估是相當有可行性的。

Nowadays, emergency department are often considered as the most efficient ways to seek medical care. However, to allocate the healthcare resource effectively, triage classification system plays an important role in assessing the severity of illness of the boarding patient at emergency department. There are some factors listed in Taiwan triage and acuity scale (TTAS) about triage classification system. And the self-report pain intensity numerical-rating scale (NRS) is one of the major modifiers of the current triage system based on the TTAS. In clinical practice, physicians and nurses have noticed the difficulty in the systematic implementation of this instrument especially for elderly people, foreigners, or patients with a low education level. This often leads to the triage nurses would select the level through his/her own observations instead of soliciting an answer from the patient. These ways would create a deviation on the consistency and validity of the triage classification system. In this paper, we have cooperation with emergency physicians in Linkou Chang Gung Memorial Hospital. We extract the multimodal behavioral signal of facial expression and vocal characteristics from patients, and model these behaviors by using machine learning models of CNN and LSTM respectively. The experimental results show that the accuracy of 77.1% and 55.7%, respectively, in the two and three classes of pain recognition. Further, in the experimental analysis, we also found that it had significant relationship with facial expression and vocal characteristics of patients.

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