Evaluating When Subscores Add Value in Psychological and Health Applications.

Many scales used in psychological and health research are designed to yield subscores, yet it is common to see total scores reported instead. One challenge of using subscores is they can lack adequate reliability due to their shortened length. However, methods originally developed for educational measurement have shown that augmenting subscores can improve reliability estimates. Augmented subscores blend the individual score with other sources of information. The present study sought to understand (a) the costs of ignoring subscores in favor of total scores and (b) the extent to which augmentation can help alleviate challenges encountered when using subscores. Data were simulated to examine when subscores should be preferred to total scores and the magnitude of improvement from using augmented subscores over non-augmented subscores. Results suggested that when a scale is designed to yield subscores, there is practical benefit to using them. In situations where subscore reliability is low, we recommend using augmentation.

Measurement Invariance in Intellectual and Developmental Disability Research.

Measurement invariance (MI) is a psychometric property of an instrument indicating the degree to which scores from an instrument are comparable across groups. In recent years, there has been a marked uptick in publications using MI in intellectual and developmental disability (IDD) samples. Our goal here is to provide an overview of why MI is important to IDD researchers and to describe some challenges to evaluating it, with an eye towards nudging our subfield into a more thoughtful and measured interpretation of studies using MI.

Toward better outcome measurement for insomnia in children with autism spectrum disorder.

LAY ABSTRACT: Insomnia, trouble falling asleep or staying asleep, is common in autistic children. In a previous report, we described the results of focus groups with parents of autistic children toward the development of the Pediatric Autism Insomnia Rating Scale. In this article, we report on the steps taken to complete the Pediatric Autism Insomnia Rating Scale. With help from the Simons Foundation registry, we collected information from parents on 1185 children with autism spectrum disorder to test the new measure. These results were evaluated using standard statistical methods such as factor analysis. To confirm the validity of the new measure, we enrolled a separate sample of 134 autistic children for a detailed assessment by video conference. This step showed that the Pediatric Autism Insomnia Rating Scale is clearly measuring symptoms of insomnia in children with autism spectrum disorder and not related problems such as hyperactivity, repetitive behavior, or anxiety. We also showed that the total score on the Pediatric Autism Insomnia Rating Scale is stable when repeated over a brief period of time. This is important because a measure that is not stable over a brief period of time would not be suitable as an outcome measure. In summary, the Pediatric Autism Insomnia Rating Scale is a brief and valid measure of insomnia in children with autism spectrum disorder that provides reliable scores.