German Center for Neurodegenerative Diseases (DZNE), Stockumer Straße 12, 58453, Witten, Germany.
School of Nursing Science, Witten/Herdecke University, Stockumer Straße 12, 58453, Witten, Germany.
BMC Geriatr. 2018 Oct 19;18(1):247. doi: 10.1186/s12877-018-0930-0.
Accurate assessment of health-related quality of life as an endpoint in intervention studies is a major challenge in dementia research. The DEMQOL (29 items) and the proxy version (32 items), which is partly based on the DEMQOL, are internationally used instruments. To date, there is no information on the structural validity, item distribution, or internal consistency for the German language version of these questionnaires.
This psychometric study is based on a secondary data analysis of a sample of 201 outpatients with a mild form of Alzheimer's disease (AD) and their informal caregivers. The informal caregivers who were interviewed were involved in the care of the person with AD several times per week. The analysis for the evaluation of the structural validity was performed using Mokken scale analysis. The internal consistency was calculated using the ρ of the Molenaar Sijtsma statistic and Cronbach's α.
For both versions, four subscales were identified: [A] "positive emotions", [B] "negative emotions", [C] "physical and cognitive functioning", and [D] "daily activities and social relationships". For both instruments, the internal consistency of all subscales was considered "good" (ρ = 0.71-0.88, α = 0.72-0.87).
The results are a first indication of good construct validity of the instruments used for the German setting. We recommend further investigations of the test-retest reliability and the inter-rater reliability of the proxy instrument.
准确评估与健康相关的生活质量作为干预研究的终点是痴呆症研究中的一个主要挑战。DEMQOL（29 项）及其代理版本（32 项），部分基于 DEMQOL，是国际上使用的工具。迄今为止，这些问卷的德语版本在结构有效性、项目分布或内部一致性方面没有信息。
这项心理测量研究基于对 201 名轻度阿尔茨海默病（AD）门诊患者及其非正式照顾者样本的二次数据分析。接受访谈的非正式照顾者每周多次参与 AD 患者的护理。使用 Mokken 量表分析对结构有效性的评估进行分析。使用 Molenaar Sijtsma 统计量的ρ和 Cronbach 的α计算内部一致性。
对于这两个版本，都确定了四个分量表：[A]“积极情绪”，[B]“消极情绪”，[C]“身体和认知功能”，和 [D]“日常活动和社会关系”。对于这两种工具，所有分量表的内部一致性均被认为是“良好”（ρ=0.71-0.88，α=0.72-0.87）。
这些结果首次表明，用于德语环境的工具具有良好的结构有效性。我们建议进一步研究代理工具的重测信度和评分者间信度。
