Sundström Björn, Johansson Sverker, Wallin Andreas
Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Huddinge, Sweden; Department of Orthopaedics and Rehabilitation, Unit of Occupational and Physical Therapy, Södersjukhuset, Stockholm, Sweden.
Department of Neurobiology, Care Sciences and Society, Division of Physiotherapy, Karolinska Institutet, Huddinge, Sweden; Women's Health and Allied Health Professionals Theme, Medical Unit Allied Health Professionals, Karolinska University Hospital, Stockholm, Sweden.
Mult Scler Relat Disord. 2025 Jan;93:106210. doi: 10.1016/j.msard.2024.106210. Epub 2024 Dec 2.
Fatigue is a subjective lack of physical and/or mental energy and is commonly perceived by people with multiple sclerosis (MS). People with MS often describe fatigue as the most troublesome MS related impairment, and it also has a negative impact on ability to initiate or maintain activities as well as work capacity and health related quality of life. The Modified Fatigue Impact Scale (MFIS) is a patient-reported outcome measurement of fatigue. The scale consists of 21 items divided into three subscales to capture the cognitive (10 items), physical (9 items) and psychosocial (2 items) dimensions of fatigue. MFIS is translated to Swedish but not evaluated for test-retest reliability for use in Swedish settings of rehabilitation or research. The aim of the study was to investigate the test-retest reliability of the total score and the scores of the subscales of the Swedish version of the MFIS in people with mild to moderate MS-disability.
Eligible study participants were people with mild to moderate overall MS-disability according to the Expanded Disability Status Scale (EDSS) - EDSS score from 2.0 to 5.5. The included participants completed the Swedish version of MFIS at two occasions, one week apart. Intraclass Correlation Coefficient (ICC) agreement was used to analyse the test-retest reliability of the total score and a quadratic weighted Cohen's kappa was used to analyse the subscale scores. Further, measurement error, smallest detectable change (SDC), and limits of agreement (LOA) were calculated for the total score of the whole sample.
A total of 54 people with MS were included in the study. The mean age was 50 years and 70 % were female. The mean overall MS-disability were 3.7 according to the EDSS, 28 of the participants had mild MS-disability (EDSS 2.0 to 3.5) and 26 of the participants had moderate MS-disability (EDSS 4.0 to 5.5). Results of test-retest reliability for the whole sample of the total score of the MFIS were acceptable with an ICC value of 0.84, a measurement error of 8.2, an SDC of 22.6 and LOA of 23.3 and -22.4. The ICC values of the total score were also acceptable for the subgroups with mild MS-disability and moderate MS-disability with ICC values of 0.83 and 0.74. The kappa values for the whole sample showed excellent or fair to good test-retest reliability of the physical, cognitive and psychosocial subscales with values of 0.83, 0.84, and 0.75.
The results of this study show that the total score of the Swedish version of MFIS is a reliable measure and a change of 23 points indicates a true change in fatigue impact in people with mild to moderate MS-disability. The test-retest reliability of the cognitive and the physical subscales were considered as excellent, and the psychosocial subscale as fair to good. The total score of the scale can be recommended for use in Swedish populations.
疲劳是一种主观的身体和/或精神能量缺乏，多发性硬化症（MS）患者常能感觉到。MS患者通常将疲劳描述为与MS相关的最麻烦的损伤，它还会对开始或维持活动的能力、工作能力以及与健康相关的生活质量产生负面影响。改良疲劳影响量表（MFIS）是一种患者报告的疲劳结局测量工具。该量表由21个项目组成，分为三个子量表，以反映疲劳的认知（10个项目）、身体（9个项目）和心理社会（2个项目）维度。MFIS已被翻译成瑞典语，但尚未在瑞典康复或研究环境中对其重测信度进行评估。本研究的目的是调查瑞典版MFIS总分及各子量表得分在轻度至中度MS残疾患者中的重测信度。
符合条件的研究参与者为根据扩展残疾状态量表（EDSS）评定为轻度至中度整体MS残疾的患者——EDSS评分在2.0至5.5之间。纳入的参与者在相隔一周的两个时间点完成瑞典版MFIS。组内相关系数（ICC）一致性用于分析总分的重测信度，二次加权科恩kappa系数用于分析子量表得分。此外，还计算了整个样本总分的测量误差、最小可检测变化（SDC）和一致性界限（LOA）。
本研究共纳入54例MS患者。平均年龄为50岁，70%为女性。根据EDSS，平均整体MS残疾评分为3.7，28名参与者为轻度MS残疾（EDSS 2.0至3.5），26名参与者为中度MS残疾（EDSS 4.0至5.5）。MFIS总分在整个样本中的重测信度结果可接受，ICC值为0.84，测量误差为8.2，SDC为22.6，LOA为23.3和-22.4。轻度MS残疾和中度MS残疾亚组的总分ICC值也可接受，分别为0.83和0.74。整个样本的kappa值显示，身体、认知和心理社会子量表的重测信度极佳或良好至中等，值分别为0.（此处原文有误，推测为0.83）、0.84和0.75。
本研究结果表明，瑞典版MFIS总分是一项可靠的测量指标，23分的变化表明轻度至中度MS残疾患者的疲劳影响发生了真实变化。认知和身体子量表的重测信度被认为极佳，心理社会子量表的重测信度良好至中等。该量表总分可推荐用于瑞典人群。
