台灣阿茲海默型失智症患者之社會功能評估量表的編制研究

Abstract

背景：適當的社會功能評估對於臨床研究與實務為相當重要之議題。過去文獻對於社會功能的定義看法不一且適用對象亦不相同，故其定義與工具的建立需依受測者年齡與疾病之特質加以修正。然而，國內現行使用之測驗工具的題目內容無法完整評估整體的社會功能，對於測驗的使用目的較乏共識，且亦缺乏合適的計分系統與樣本，不利於臨床上客觀評估阿茲海默型失智症患者之社會功能缺損程度。目的：本研究主要目的為編製台灣阿茲海默型失智症患者之社會功能評估量表（SFSAD），主要目標為：一、量表之編製；二、評估本量表的心理計量特性；三、探討本量表之臨床效用。方法：本研究根據文獻回顧與專家經驗進行題目發展與量表修訂，該量表採照顧者評估方式進行。本研究受試者包括142名不同嚴重度之阿茲海默型失智症（AD）與30名輕度認知障礙（MCI）患者及其主要照顧者，以及50名正常老年人。受試者均接受簡易智能狀態測驗（MMSE），並由病人家屬或由正常老年人自行填答本量表，而其中30名AD患者亦接受工具性日常生活活動能力量表（IADL）與巴氏量表（Bathel ADL）評估來檢驗SFSAD之效度，並於一個月後進行再測以檢驗信度。結果：經修訂後本量表包含4個分量表，總計20題。信度結果顯示SFSAD具穩定的內部一致性（Cronbach's α = .97）與再測信度（r = .99）。效度部份，SFSAD具適當的內容效度以及良好的效標關聯效度，與MMSE、IADL、Barthel ADL皆呈顯著負相關。對於區分不同失智嚴重度之AD患者、MCI患者、及正常老年人，SFSAD具合宜的區辨效度，且其驗證性因素分析結果亦支持四因素之模型結構。臨床應用方面，本量表之分數切截點可有效判斷社會功能缺損之有無，且總量表與各分量表分數可偵測MCI與AD不同階段的病程改變。結論：SFSAD為一具備良好信效度之社會功能評估工具，在臨床實務上則提供一整體社會功能分數與各分量表分數指標，以及社會功能缺損有無之切截點。因此建議將該量表納入AD及MCI患者例行之神經心理功能檢查，以利臨床工作者進行鑑別診斷、監控病程改變、以及評估介入效果。

Background: Social-functioning evaluation is essential for clinical service. Previous studies have employed various definitions of social functioning; however, the definitions should be modified and the instruments should be developed based on different characteristics of subjects (e.g., age and disease). For the purpose of objectively evaluating social-functioning impairments in the patients with Alzheimer's disease (AD), the existing instruments lack of representative contents based on the definition of social functioning. Moreover, lack of consensus about purposes of use and lack of adequate scoring systems and samples, also limit the clinical applications. Objective: The study was aimed to develope a social functioning scale for patietns with AD — the Social Functioning Scale for Alzheimer's Disease (SFSAD). The specific objectives were to explore: (1) the establishment of the SFSAD, (2) the issues of psychometric properties, and (3) the issue of clincial utilities. Methods: The items in the SFSAD were complied based on literature review and experiences of experts, and the informant report was used. The study collected142 AD patients with different severity of dementia and 30 patients with amnestic mild cognitive impairment (aMCI), and 50 normal controls. The caregivers of patient groups were also recruited and requested to fill in the SFSAD, whereas the normal controls filled in the scale based on self-report. All patients and normal controls received the Mini-mental state examination (MMSE), and 30 patients with AD also received the evaluation of the Instrumental Activities of Daily Living Scale (IADL) and the Barthel Activities of Daily Living Index Scale (Barthel ADL) to examine validity. Meanwhile, the caregivers of these 30 patients received retest after one month later. Results: The SFSAD had 20 items in 4 subscales. It showed a high degree of the internal consistency coefficients (Cronbach's α = .97) and test-retest (r = .99) reliability. The content validity of the SFSAD was desirable, and the criterion-related validity was demonstrated by the significant correlations between the SFSAD and measures of the MMSE, the IADL, and the Barthel ADL. Moreover, discriminant validity was further confirmed by the significant differences among AD patients in terms of the degree of demented severity, aMCI patients, and normal controls. Our findings also supported the structure of the four-factor hypothesized model. Clinically, the cut-off points could effectively determine whether or not the patients have significant social-functioning impairments, and the total score and subscale scores could be used for detecting the progression in different stages of AD. Conclusion: The SFSAD is an inventory for evaluating social functioning with sound psychometric properties. In consideration of its clinical utilities, the present study provided the total score and subscale scores as the indices of social-functioning impairments, and cut-off points of determining functional deficits were also presented. The SFSAD is practical to use for differential diagnosis, monitoring progression, and outcome evaluation, and it is suggested to include this scale in the routine neuropsychological assessment of patients with MCI or AD