Early Vocabulary Inventory for Mandarin Chinese

1. Introduction

Early vocabulary development is not only an important milestone in children’s language development; it is also a reliable predictor of children’s later language skills. The study of this subject has significant implications, therefore, not only for normal language development, but also for language delays and other abnormally developing patterns in the clinical context. In response to the significance of the early childhood lexicon, researchers have developed vocabulary norms in a variety of languages. Among the existing vocabulary norms, the parental report has been the most widely used instrument, because it is less time consuming, easy to conduct, and easy to obtain in large quantities in a relatively short amount of time. As its name implies, parental report requires parents to judge whether their children can understand or produce the words in a given wordlist. Fenson et al. (1994), and Dale and Fenson (1996) pioneered this line of work. They named their parental report norm the Communicative Development Inventory(CDI), with which they investigated American children’s comprehension and production vocabulary between the ages of 0;8 (8 months) and 2;4 (2 years 4 months). They have also made available a Web-based interface that contains the English and Spanish lexical norms at www.sci.sdsu.edu/cdi/.

Building on the original CDI, a number of researchers have developed different versions of the CDI in other languages and linguistic variants, such as British English (Hamilton, Plunkett & Schafer, 2000), Spanish (JacksonMaldonado, Thal, Marchman, Bates & Gutierrez-Clellen, 1993), and New Zealand English (Reese & Read, 2000). However, there are no published CDI norms yet for Mandarin Chinese. Given the language-specific properties of Chinese, and the differences between Chinese and Indo-European languages in acquisition (Li, Tan, Bates & Tzeng, 2006), it is important to develop similar measures for Mandarin Chinese.

A few studies have used parental reports to evaluate Chinese children’s early vocabulary development. Wu (1997) used a version of CDI in her dissertation research of Chinese children’s lexical development. However, the extent to which her results truly capture early Chinese lexicon is questionable, because her child participants all resided in the U.S.A. (30 children of Chinese immigrants in Boulder, Colorado) and their parents had mixed linguistic and cultural backgrounds (from Mainland China, Taiwan and Singapore). Many were bilingual Chinese-English speakers or spoke English as a second language. In addition, some items in the questionnaire list were uncommon to Mandarin-speaking children in Mainland China—for example, 脚踏车 (jiaotache, bicycle); 窗户帘(chuanghulian, curtain); 邮差 (youchai, postman); 警员 (jingyuan, policeman). Some were also low-frequency words in the spoken language, such as 打击 (daji, hit); 关闭 (guanbi, close); 摇动 (yaodong, move); and 攀登 (pandeng, climb). Part of the problem might be that Wu simply translated the original English word list into Chinese, so it cannot be used as a reliable tool to faithfully assess Mandarin-speaking children’s early vocabulary development. In light of this problem, Tardif and her colleagues (Liang et al., 2001; Tardif, Gelman & Xu, 1999) developed their own versions of Chinese CDI to examine children learning Mandarin and Cantonese. Although Tardif et al.’s Chinese CDI forms represented an improvement over Wu’s, two problems still limited the use of their CDIs. One is the same as that in Wu’s CDI; namely, the problem that some words were simply translations of the original English words and were therefore not colloquial to Mandarin-speaking children. The other is that the actual lexical norms are not as readily available to researchers as are the English lexical norms. Thus, it is difficult to either use or validate their norms in language acquisition in a variety of research contexts.

In this article, we report data collected from 884 Chinese families in Beijing (children’s age range, 12~30 months) and describe the ways in which we constructed the early vocabulary inventory for Mandarin Chinese. We attempt to correct the problems seen in the Wu (1997) and Tardif et al. (1999) versions of the Chinese CDI in order for our word lists to reflect the language characteristics and faithfully capture early vocabulary development in Mandarin Chinese. It is important to consider validity issues in constructing early vocabulary inventories, and our study indicates that a significant portion of the words are not shared between English and Chinese for the early vocabulary (see the Method section and the archived materials). At the same time, we attempt to make the actual lexical norm readily available to the general research community, via the Internet.