巴金森氏病（Parkinson's disease, PD）在發病初期就可能因神經肌肉的損傷，而出現語言溝通上的障礙，PD在發病初期就可能因神經肌肉的損傷，而出現語言溝通上的障礙甚至影響吞嚥。研究發現，大多數PD患者會合併出現言語溝通上的問題，然而卻只有59% 的病人接受語言治療的介入。PD患者對於自身言語障礙的感知有缺陷，若能覺察到自身言語障礙的訊息將有助於提高治療的動機；此外言語溝通是真實的生活情境中產生的行為， PD患者的言語障礙會影響生活滿意度，而臨床常用的評估工具以儀器檢查以及知覺性言語評量，有其客觀性，但無法反應PD患者對溝通障礙的感知以及自身在溝通情境的困難。PD的言語涵蓋多面向的障礙，具有其特殊性，需要全面性且及敏感性的篩檢工具以早期偵測出PD患者的言語障礙，早期轉介語言治療，幫助患者對言語功能維持以及溝通障礙的自我管理。然而台灣只有少數有關PD患者言語障礙的表現的相關研究，因此本研究主要的目的是發展「巴金森氏病言語障礙篩檢量表(Chinese Screening Tool for Speech Disorders in Patients with Parkinson's Disease, CSSDPD)」，檢定量表的心理測量特性，並探討台灣PD患者言語障礙的表現。
研究主題一為編制CSSDPD，本研究依據PD患者言語溝通問題障礙的症狀以及文獻的探討，歸納出量表的四個評量面向，「構音與口腔表達動作功能」、「發聲及共鳴」、「音韻及節律」、「情緒與非口語溝通行為」。經過專家們的意見與建議，量表總共有36題，最後以93位原發型PD患者作為研究樣本進行項目分析，並以各題與總量表相關程度≧0.4為選題標準，再刪除語意相似及難以理解的題目，最後CSSDPD量表共24題。
研究主題二為建立CSSDPD的信效度，研究樣本為93位PD受試者，得到量表的內部一致性α=0.91，其中以37位受試者作為再測信度樣本，得到組內相關性ICC=0.91。以VHI-10及MDS-UPDRS第二部分與語言相關的2.1題與SSDPD總量表的相關性作為校標關聯效度的指標，分別得到r=0.83及0.78；以母音/a/、/i/、/u/的聲學參數與CSSDPD量表總分的相關性作為聚斂效度的指標，最後再以PD受試者在H &Ｙ的運動障礙分級作為區辨效度的檢驗，研究發現CSSDPD總量表的得分在不同運動障礙等級皆達顯著差異。
研究主題三為檢驗CSSDPD篩檢的精確性，以及探討PD患者的言語障礙表現。PD組為93位原發型PD患者，對照組為76位年齡>55歲的健康老人，本研究的篩選正確機率AUC值為0.955(95%信賴區間為0.927-0.983;漸進顯著性p<0.001)。本研究之最佳切截分數為35.5，其敏感度0.849，特異度為0.947，在此切截分數之上即可懷疑有言語障礙。本研究以PD受試者在CSSDPD的總分53.18為中點。標準差18.78為級距將PD患者的得分分為五個等級，等級愈高言語障礙愈嚴重；由變異數分析檢定得知不同等級的PD患者在CSSDPD的得分達顯著差異。另外以PD患者在CSSDPD每題的得分平均得知，PD患者在四個面向的言語障礙程度最嚴重為「發聲及共鳴」，依序為「情緒與非口語溝通行為」、「構音與口腔表達動作功能」、「音韻及節律」。另外，變異數分析檢定顯示，PD患者在發/a /、/i/、/u/時的聲學參數，jitter %、 shimmer% 和HNR在H &Ｙ四個階段間的表現，皆未達顯著差異；多數有關PD患者的聲學參數的研究亦顯示PD患者的聲學表現並不一致。總結以上的研究發現，與目前多數的研究結果相似。其次本研究亦發現當PD患者在自覺說話時臉部表情減少時，將會影響溝通的動機，因此在治療介入時應重視PD患者在情緒與非口語溝通行為所以引起的言語障礙，期以提供合適的治療策略。

Parkinson's disease (PD) is a chronic degenerative disease of the central nervous system, with the main symptom being the impairment of motor functions. However, patients with PD also present hypokinetic dysarthria which include unintelligibility and/or unnaturalness of speech with the problems of phonation, respiration, resonance, articulation, and prosody. These symptoms will gradually affect their communication. Studies suggested that PD patients have a deficit in their perception of their speech disorders. If PD patients are aware of their own speech disorders, it will help to improve their motivation to receive treatment. Language communication occurs in real life situations, and problems in language communication can affect the quality of life of patients with PD. However, the commonly used clinical assessment tools, such as instrumental examination and perceptual analysis, though objective, do not reflect the perception of communication impairment and the difficulties of the PD patient in communication. The speech disorders in PD patients cover a wide range of impairments and is unique in that it requires comprehensive and sensitive screening tools for early detection of speech disorders, early referral for speech therapy, and self-management of speech function and communication impairment. Yet, there are only a few studies focused on the manifestation of speech disorders in PD patients in Taiwan. Therefore, the main purpose of the dissertation is to develop a screening tool for Chinese speaking patients with Parkison’s disease "Chinese Screening Tool for Speech Disorders in Patients with Parkinson’s Disease (CSSDPD)" to identify markers of speech disorders in patients with PD with specific aims the followings.
Specific aim 1: to develop the CSSDPD. The initial list of potential checklist items was based on clinical diagnostic index and review of the literature related to speech disorders in patients with PD. The content and items on the scale were revised or deleted according to expert's replies and comments. Consequently, the scale comprised four assessment domains: "Articulation and Oral Motor Function," "Phonation and Resonation," "Prosody and Rhythm," and "Emotional and Nonverbal Communication Behavior," including 36 items in all. Finally, item analysis were tested with a sample of PD subjects (n=93). In terms of the correlation between individual items and total scores is at least 0.4, as well as items with similar meaning or items that were difficult to understand, were deleted. In total, there were 24 retained items.
Specific aim 2: to determine the reliability and validity of the CSSDPD. Ninety-three patients with PD participated in this study. The Cronbach α coefficient of the scale was 0.91. A total of 37 PD participants were selected as samples for assessing test-retest reliability. The overall ICC of the CSSDPD was 0.91. The correlation between VHI-10 and CSSDPD, as well as the correlation between Questions 2.1 of the MDS-UPDRS and CSSDPD were examined as the criterion-related validity of the scale. They are 0.83 and 0.78, respectively. Pearson’s correlation coefficient analysis was conducted to determine the acoustic parameters of patients with PD while they pronounced the three vowels /a/, /i/, and /u/ and to examine the relevance between the acoustic parameters and the CSSDPD, which are used as the convergent validity of the scale. Discriminant validity of the scale is examined by testing the CSSDPD scores of PD patients based on the H & Y stages 1-4. This study showed that there was a significant difference in them.
Specific aim 3: to test the accuracy of the CSSDPD and explore the speech characteristics of patients with PD based on the CSSDPD. Ninety-three patients with primary PD were included in the PD group and seventy-six healthy older adults aged > 55 years were included in the control group. The AUC of this study was 0.955 (95% CI, 0.927-0.983; asymptotic significance p < 0.001). The best cutoff score for CSSDPD was 35.5, with a sensitivity of 0.849 and a specificity of 0.947. Patients with scores above the cutoff value were suspected of having speech disorders. The mean total score (53.18) of PD subjects in CSSDPD was used as the midpoint and the standard deviation (18.78) was used as the interval to classify the scores of PD patients into five levels, a higher level indicated more severe speech disorders. Variance analysis showed that there were significant differences between the scores of the levels. In addition, the total score of each question was averaged to see the difference in the performance of PD subjects in the 4 domains, where the data from the study showed that PD subjects showed the most severe disorder in“Phonation and Resonation,” followed by“Emotional and Nonverbal Communication Behaviors,”“Articulation and Oral Motor Function,”and“Prosody and Rhythm.” However, the phonological variables of /a /, /i/, /u/, jitter %, shimmer% and Harmonics-to-Noise ratio were not significantly different among the 4 stages of H & Y. Acoustic studies have found inconsistencies in the correlation between acoustic parameters in patients with PD. In summary, the results of this study are similar to most existing studies. In addition, PD patients have noted to reduce facial expression during their conscious speech, which may affect their motivation of communication. Therefore, the speech disorders caused by emotional and nonverbal communication behaviors of PD patients should be taken into consideration during therapeutic intervention in order to provide appropriate treatment strategies.

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