University of Aveiro, Department of Education and Psychology, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal.
Sleep Medicine Unit, Centro Cirúrgico de Coimbra, 3045-089, Coimbra, Portugal.
Sleep Med. 2023 Sep;109:261-269. doi: 10.1016/j.sleep.2023.07.008. Epub 2023 Jul 17.
OBJECTIVE/BACKGROUND: The Epworth Sleepiness Scale (ESS) is one of the most used self-reported instruments to assess sleepiness. Thus, several adaptations into different Languages have been performed worldwide over the years. The scale has produced disparate psychometric properties when applied in different settings. In the current study, our aim was to perform a Reliability Generalization meta-analysis of the Cronbach᾽s alphas of all published studies on ESS, specifically with a psychometric focus.
PATIENTS/METHODS: Three reference databases (Scopus, PubMed and Web of Science) were searched since 1991 to October 2022 and all the records on psychometric or validation studies that reported Cronbach's alphas, from clinical and nonclinical groups, were included. In total, data from 46 publications (63 estimates) were extracted, comprising 92,503 participants.
Using a Random-Effects Model, the cumulative Cronbach's alpha for the 63 estimates was about 0.82 (CI: 0.798, 0.832) which can be considered as a good measure. However, and as expected, it was observed a high level of heterogeneity (I = 98.96%). Moderation analyses considering setting, date, continent, risk of bias, sex, age and language were performed in order to account for the heterogeneity. Even so, only the variables study setting and continent were significant, and had little importance in explaining the heterogeneity.
The ESS is a reliable tool to measure sleepiness; however, further studies are needed to investigate what variables might explain the observed variability. Moreover, it will be important to include empirical studies beyond psychometric ones.
目的/背景：Epworth 嗜睡量表（ESS）是评估嗜睡最常用的自我报告工具之一。因此，多年来，世界各地已经进行了多次翻译成不同语言的改编。该量表在不同环境下应用时产生了不同的心理测量特性。在本研究中，我们的目的是对所有已发表的 ESS 研究的 Cronbach᾽s 阿尔法进行可靠性综合元分析，特别是从心理测量的角度进行分析。
患者/方法：从 1991 年到 2022 年 10 月，我们在三个参考文献数据库（Scopus、PubMed 和 Web of Science）中进行了搜索，并纳入了所有报告 Cronbach 阿尔法的心理测量或验证研究的记录，包括临床和非临床组。总共提取了 46 篇出版物（63 个估计值）的数据，包含 92503 名参与者。
使用随机效应模型，63 个估计值的累积 Cronbach᾽s 阿尔法约为 0.82（CI：0.798，0.832），这可以被认为是一个很好的衡量标准。然而，正如预期的那样，观察到了高度的异质性（I = 98.96%）。为了解释异质性，我们进行了考虑设置、日期、大陆、偏倚风险、性别、年龄和语言的调节分析。即便如此，只有研究设置和大陆这两个变量是显著的，并且对解释异质性的重要性不大。
ESS 是一种可靠的测量嗜睡的工具；然而，需要进一步的研究来调查哪些变量可能解释观察到的可变性。此外，除了心理测量研究之外，纳入实证研究将是重要的。
