Abstract：
Single-case experimental designs (SCEDs) have grown in popularity in the fields such as education, psychology, medicine, and rehabilitation. Although SCEDs are valid experimental designs for determining evidence-based practices, they encounter some challenges in analyses of data. One of these challenges, missing data, is likely to be occurred frequently in SCEDs research due to repeated measurements over time. Since missing data is a critical factor that can weaken the validity and generalizability of a study, it is important to determine the characteristics of missing data in SCEDs, which are especially conducted with a small number of participants. In this regard, this study aimed to describe missing data features in SCEDs studies in detail. To accomplish this goal, 465 published SCEDs studies within the recent 5 years in six journals were included in the investigation. The overall results showed that the prevalence of missing data among SCEDs articles in at least one phase, as at least one data point, was approximately 30%. In addition, the results indicated that the missing data rates were above 10% within most studies where missing data occurred. Although missing data is so common in SCEDs research, only a handful of studies (5%) have handled missing data; however, their methods are traditional. In analyzing SCEDs data, several methods are proposed considering missing data ratios in the literature. Therefore, missing data rates determined in this study results can shed light on the analyses of SCEDs data with proper methods by improving the validity and generalizability of study results.
摘要：
单案例实验设计(SCED)在教育、心理学,医学,和康复。尽管SCED是确定循证实践的有效实验设计，他们在数据分析中遇到了一些挑战。这些挑战之一，缺少数据，由于随着时间的推移重复测量，在SCED研究中可能经常发生。由于数据缺失是削弱研究有效性和普遍性的关键因素，确定SCED中缺失数据的特征很重要，特别是与少数参与者进行的。在这方面,本研究旨在详细描述SCED研究中缺失的数据特征.为了实现这个目标,调查包括了最近5年内在6种期刊上发表的465项SCED研究。总体结果表明，SCED文章中至少有一个阶段的数据缺失率，作为至少一个数据点，约为30%。此外,结果表明,在发生数据缺失的大多数研究中,数据缺失率超过10%.尽管缺失数据在SCED研究中很常见，只有少数研究(5%)处理了缺失的数据；然而，他们的方法是传统的。在分析SCED数据时，在文献中，考虑到缺失数据率，提出了几种方法。因此,本研究结果中确定的数据缺失率可以通过提高研究结果的有效性和普适性,为采用适当方法分析SCED数据提供依据.
