Rett syndrome (RTT) is a neurodevelopmental disorder that primarily affects females. Recent work indicates the potential for disease modifying therapies. However, there remains a need to develop outcome measures for use in clinical trials. Using data from a natural history study (n = 1,075), we examined the factor structure, internal consistency, and validity of the clinician-reported Motor Behavior Assessment scale (MBA). The analysis resulted in a five-factor model: (1) motor dysfunction, (2) functional skills, (3) social skills, (4) aberrant behavior, and (5) respiratory behaviors. Item Response Theory (IRT) analyses demonstrated that all items had acceptable discrimination. The revised MBA subscales showed a positive relationship with parent reported items, age, and a commonly used measure of clinical severity in RTT, and mutation type. Further work is needed to evaluate this measure longitudinally and to add items related to the RTT phenotype.

中文翻译：

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运动行为评估量表的心理计量学评估，作为瑞特综合症临床试验的结果指标。

Rett综合征（RTT）是一种主要影响女性的神经发育障碍。最近的工作表明了疾病改良疗法的潜力。但是，仍然需要开发用于临床试验的结果指标。使用自然史研究（n = 1,075）中的数据，我们检查了临床医生报告的运动行为评估量表（MBA）的因素结构，内部一致性和有效性。该分析产生了五因素模型：（1）运动功能障碍，（2）功能技能，（3）社交技能，（4）异常行为和（5）呼吸行为。项目响应理论（IRT）分析表明，所有项目都具有可接受的辨别力。修订后的MBA子量表与父母报告的项目，年龄，RTT的临床严重程度和突变类型的常用量度呈正相关。