Measuring changes in language skills (Kwok et al., 2022)

<strong>Purpose: </strong>Norm-referenced, standardized measures are tools designed to characterize a child’s abilities relative to their same-age peers, but they also have been used to measure changes in skills during intervention. This study compared the psychometric properties of four types of available scores from one commonly used standardized measure, the Preschool Language Scales–Fifth Edition (PLS-5), to detect changes in children’s language skills during and after a language intervention. <strong>Method:</strong> This study included data from 110 autistic children aged 18–48 months whose mother participated in an 8-week parent-mediated language intervention. Children’s language skills were measured at 3 time points using the PLS-5. Changes in children’s expressive and receptive language skills were calculated using raw scores, standard scores, age equivalents, and growth scale values (GSVs). <strong>Results: </strong>Analysis of raw scores, age equivalents, and GSVs indicated significant improvement in the scores of autistic children in both receptive and expressive language throughout the study (i.e., during the intervention period and in the 3-month period after the intervention). Standard scores suggested improvement only in the receptive language scale during the intervention period. Standard scores showed a floor effect for children who scored at −3 <em>SD</em> below the mean. <strong>Conclusions:</strong> Findings suggested that GSVs were not only psychometrically sound but also the most sensitive measure of direct changes in skills compared to raw, standard, and age-equivalent scores. Floor effects may limit the sensitivity of standard scores to detect changes in children’s skills. Strengths, limitations, and interpretations of each of the scoring approaches in measuring changes in skills during intervention were discussed. <strong>Supplemental Material S1. </strong>Effect size of changes from intervention as measured by each scoring approaches (with nonparametric Wilcoxon signed-rank test). Kwok, E., Feiner, H., Grauzer, J., Kaat, A., &amp; Roberts, M. Y. (2022). Measuring change during intervention using norm-referenced, standardized measures: A comparison of raw scores, standard scores, age equivalents, and growth scale values from the Preschool Language Scales–Fifth Edition. <em>Journal of Speech, Language, and Hearing Research</em>. Advance online publication. https://doi.org/10.1044/2022_JSLHR-22-00122

**目的：** 常模参照标准化测评工具旨在刻画儿童相较于同龄同伴的能力水平，同时也被用于评估干预过程中技能的变化。本研究针对一款常用的标准化测评工具——学前语言量表第五版（Preschool Language Scales–Fifth Edition，PLS-5），比较其四种常用得分的心理测量学特性，以检测语言干预期间及干预后儿童语言技能的变化。
**方法：** 本研究纳入了110名年龄介于18至48个月的自闭症儿童，其母亲参与了一项为期8周的家长介导语言干预。研究采用PLS-5在三个时间点对儿童的语言技能进行测评。通过原始分、标准分、年龄等值分以及成长量表值（growth scale values，GSVs）计算儿童表达性与接受性语言技能的变化。
**结果：** 对原始分、年龄等值分及成长量表值的分析显示，在整个研究周期（干预期间及干预后3个月）内，自闭症儿童的接受性与表达性语言得分均出现显著提升。标准分仅在干预期间的接受性语言维度上呈现提升趋势。当儿童得分低于平均分3个标准差（−3 SD）时，标准分存在地板效应。
**结论：** 研究结果表明，相较于原始分、标准分与年龄等值分，成长量表值不仅具备良好的心理测量学特性，同时也是检测技能直接变化最为敏感的指标。地板效应可能会限制标准分检测儿童技能变化的敏感性。本研究还讨论了各类得分方法在评估干预期间技能变化时的优势、局限与解读方式。
**补充材料S1：** 各类得分方法所测得的干预后变化的效应量（采用非参数Wilcoxon符号秩检验）。
Kwok, E., Feiner, H., Grauzer, J., Kaat, A., & Roberts, M. Y. (2022). 采用常模参照标准化测评工具评估干预期间的技能变化：学前语言量表第五版的原始分、标准分、年龄等值分与成长量表值比较。*Journal of Speech, Language, and Hearing Research*，预印在线发表。https://doi.org/10.1044/2022_JSLHR-22-00122