University of Kansas, Lawrence, KS 66045, USA.
J Speech Lang Hear Res. 2010 Apr;53(2):333-49. doi: 10.1044/1092-4388(2009/08-0183).
The mean length of children's utterances is a valuable estimate of their early language acquisition. The available normative data lack documentation of language and nonverbal intelligence levels of the samples. This study reports age-referenced mean length of utterance (MLU) data from children with specific language impairment (SLI) and children without language impairments.
Of the 306 child participants drawn from a data archive, ages 2;6-9;0 (years;months), 170 were in the SLI group and 136 were in the control group. There were 1,564 spontaneous language samples collected, and these were transcribed and analyzed for sample size and MLU in words and morphemes. Means, standard deviations, and effect sizes for group differences are reported for MLUs, along with concurrent language and nonverbal intelligence assessments, per 6-month intervals.
The results document an age progression in MLU words and morphemes and a persistent lower level of performance for children with SLI.
The results support the reliability and validity of MLU as an index of normative language acquisition and a marker of language impairment. The findings can be used for clinical benchmarking of deficits and language intervention outcomes as well as for comparisons across research samples.
儿童话语的平均长度是衡量其早期语言习得的一个重要指标。现有的规范数据缺乏对样本语言和非语言智力水平的记录。本研究报告了来自特定语言障碍（SLI）儿童和无语言障碍儿童的年龄参照平均话语长度（MLU）数据。
在从数据档案中抽取的 306 名儿童参与者中，年龄为 2；6-9；0（年；月），其中 170 名在 SLI 组，136 名在对照组。共收集了 1564 个自然语言样本，并对这些样本进行了转录和分析，以确定样本量和单词和词素的 MLU。报告了 MLU 的平均值、标准差和组间差异的效应量，以及每 6 个月进行的语言和非语言智力评估。
结果记录了 MLU 单词和词素的年龄进展，以及 SLI 儿童持续较低的表现水平。
研究结果支持 MLU 作为规范语言习得的指标和语言障碍的标志物的可靠性和有效性。研究结果可用于临床评估缺陷和语言干预结果的基准，以及用于跨研究样本的比较。
