PURPOSE The purpose of this study was to investigate the diagnostic accuracy of two measures derived from spontaneous language samples, mean length of utterance in words (MLUw) and percentage of grammatical utterances (PGU), in identifying developmental language disorder (DLD) in Spanish-English bilingual children. We examined two approaches: best language and total language. METHOD The participants in this study included 74 Spanish-English bilingual children with (n = 36) and without (n = 38) DLD. Language samples were elicited through a story retell and story generation task using Frog wordless picture books in English and Spanish. Stories were transcribed and coded using the Systematic Analysis of Language Samples (Miller & Iglesias, 2020) to extract MLUw and PGU in both languages. RESULTS Logistic regression analyses suggested that a model that included PGU, MLUw, and age achieved the best diagnostic accuracy in predicting group membership. Both approaches, best language and total language, had fair diagnostic accuracy. CONCLUSIONS In combination, PGU and MLUw seem to be useful diagnostic tools to differentiate bilingual children with and without DLD. Clinical implications and usability are discussed.

中文翻译：

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双语儿童语法和话语长度的诊断准确性。


目的 本研究的目的是调查从自发语言样本中得出的两项指标的诊断准确性，即单词平均话语长度 （MLUw） 和语法话语百分比 （PGU），在识别西班牙语-英语双语儿童发育语言障碍 （DLD） 方面的准确性。我们研究了两种方法：best language 和 total language。方法 本研究的参与者包括 74 名患有 （n = 36） 和没有 （n = 38） DLD 的西班牙语-英语双语儿童。通过使用 Frog 的英语和西班牙语无字图画书的故事复述和故事生成任务来引出语言样本。使用语言样本的系统分析（Miller & Iglesias，2020）对故事进行转录和编码，以提取两种语言的MLUw和PGU。结果 Logistic 回归分析表明，包括 PGU 、 MLUw 和 age 的模型在预测群体成员身份方面取得了最佳诊断准确性。Best Language 和 total language 这两种方法都具有相当的诊断准确性。结论 PGU 和 MLUw 联合使用似乎是区分双语儿童 DLD 和不 DLD 的有用诊断工具。讨论了临床意义和可用性。