Latent Structure of Sluggish Cognitive Tempo and ADHD Symptoms

描述（由申请人提供）：我们建议评估一种评估迟缓认知节奏（SCT）的新方法，并表征其与DSM-IV ADHD症状相关的潜在结构。SCT是一种不同于多动-冲动和注意力不集中的综合征。它与注意力不集中型多动症有关。SCT的最初特征是白日梦，看起来迟钝或昏昏欲睡。该构念已被扩大为信息处理缓慢、工作记忆不一致、难以保持警觉和觉醒、难以保持定向、运动缓慢和被动倾向（主动性低）。SCT的研究一直受到未解决的测量问题的限制。目前尚无基于经验的评估SCT的方法。大多数研究只使用了2-3个SCT项目，远远少于推荐的潜在构念的可靠测量（Devellis, 2003）。另一个限制是SCT项目是非特异性的，可能与一系列短暂状态（疲劳、睡眠剥夺等）和其他精神病理状况有关。如果不加以纠正，SCT项目的这一方面会虚假地增加SCT的观察患病率，以及SCT与内化疾病之间的明显合并症。本研究旨在通过评估基于访谈者的诊断访谈，即儿童迟缓认知节奏访谈（K-SCT）来弥补文献中的这一空白。K- SCT包含一个扩展的项目池（16个项目）。它提示采访者将被认可的项目分类为主要的、次要的或短暂的状态。我们将使用心理测量标准、因素分析和潜在分类分析来评估项目，并探索将SCT引入ADHD症状池可能产生的分类学影响。ADHD-I一直被批评为异质性，并被错误地嵌套在外化障碍中。这些问题是仅仅依靠多动冲动症状的数量作为区分类型的标准的后果。SCT项目可以根据一系列特征症状来定义ADHD-I，而不是像ADHD-C一样表现出注意力不集中的症状，但却没有多动症-冲动的6种症状。如果SCT确实是无多动的注意缺陷障碍典型病例的特征，那么扩展的ADHD症状池（ADHD+SCT）的潜在建模可能会将病例聚集到组内相似性更多，组间相似性更少的组中，而不是使用当前的系统。这将有助于确定不同类型之间的遗传和治疗反应差异。公共卫生相关性：这项拟议的研究将评估一种新的诊断缓慢认知节奏（SCT）的方法，该方法克服了目前的几个限制。它还将研究SCT如何与DSM-IV中现有的ADHD症状相适应。研究结果可能为更新ADHD的诊断标准提供指导，从而加强识别不同类型的基因和治疗反应差异的努力。

DESCRIPTION (provided by applicant): We propose to evaluate a new method of assessing Sluggish Cognitive Tempo (SCT), and to characterize its latent structure in relation to DSM-IV symptoms of ADHD. SCT is a syndrome that is distinct from Hyperactivity-Impulsivity and Inattention. It is associated with inattenttive types of ADHD. The original features of SCT were daydreams and seems sluggish or drowsy. The construct has been broadened descriptively refer to slow information processing, inconsistent working memory, difficulty maintaining alertness and arousal, difficulty maintaining orientation, and tendency toward slow movement and passivity (low initiative). Research into SCT has been constrained by unresolved measurement issues. No empirically-based method of assessing SCT is available. Most studies have used only 2-3 SCT items, a number far fewer than recommended for reliable measurement of a latent construct (Devellis, 2003). Another limitation is that SCT items are non-specific and may be related to a range of transitory states (fatigue, sleep deprivation, etc.) and other psychopathological conditions. Left uncorrected, this aspect of SCT items would spuriously increase the observed prevalence of SCT and the apparent comorbidity between SCT and internalizing disorders. The proposed study seeks to remedy this gap in the literature by evaluating an interviewer- based diagnostic interview, the Kiddie Sluggish Cognitive Tempo Interview (K-SCT). The K- SCT contains an expanded item pool (16 items). It prompts the interviewer to classify endorsed items as being either primary, or as secondary to another condition or to a transient state. We will use psychometric criteria, factor analysis, and latent class analysis to evaluate items and to explore what the nosological effects may be of introducing SCT into the ADHD symptom pool. ADHD-I has been criticized for being heterogeneous and for being incorrectly nested within the externalizing disorders. Such problems are the consequences of relying solely on the number of hyperactivity-impulsivity symptoms as the criterion for differentiating types. SCT items may make it possible to define ADHD-I in terms of a set of characteristic symptoms, rather than as children who display the same symptoms of inattention as ADHD-C, but fall short of 6 symptoms of hyperactivity-impulsivity. If SCT indeed characterizes the prototypical case of attention deficit disorder without hyperactivity, then latent modeling of an expanded pool of ADHD symptoms (ADHD+SCT) may aggregate cases into groups with more within-group similarities and fewer between-group similarities than is seen using the current system. This would facilitate the identification of genetic and treatment response differences among types. PUBLIC HEALTH RELEVANCE: The proposed study will evaluate a novel diagnostic procedure for Sluggish Cognitive Tempo (SCT) that overcomes several current limitations. It will also examine how SCT fits in with the existing ADHD symptoms in DSM-IV. The results may provide a guide for updating the diagnostic criteria for ADHD in a way that would enhance efforts to identify genetic and treatment response differences among the types.