Vocabulary Instruction, Reading Comprehension, and Student Retention: a Review of Literature

The following literature review is an analysis of the relationship of vocabulary instruction, reading comprehension, and student retention. Vocabulary can affect comprehension; however the most effective method of vocabulary instruction has yet to be determined. Context, semantic mapping, and a combination of instructional approaches are examined. Many types of vocabulary instruction can have a positive effect on comprehension, particularly when these methods rely on multiple exposures to a word and interactive approaches. Student retention and level of word knowledge need to be investigated further. VOCABULARY, COMPREHENSION, RETENTION 4 Chapter I: Introduction Researchers suggest that early elementary students’ word knowledge is a determinant of reading comprehension both in early elementary school and throughout their schooling (Juel and Deffes, 2004). Specifically, one such argument is “The vocabulary of entering first graders predicts not only their word reading ability at the end of first grade but also their 11 Statement of the Problem grade reading comprehension” (p. 31). This stated relationship between word knowledge and reading comprehension dates back to Thorndike’s (1917) landmark study and other replication studies as well (Becker, 1977; Cunningham & Stanovich, 1997; Biemiller & Slonim, 2001). While the relationship between vocabulary and reading comprehension appears to be established, instructional methods to effectively increase students’ word knowledge and comprehension are not. Determining which instructional method or methods will positively affect students’ word knowledge, reading comprehension, and retention of these skills is both timely and significant. Jitendra, Edwards, Sacks, & Jacobson (2004) concluded, “vocabulary and word knowledge can contribute to improved comprehension, and it provides a sound rationale for increased emphasis on vocabulary instruction” italics added (p. 299). Bromley (2007) reported, “Vocabulary is a principle contributor to comprehension, fluency, and achievement” italics added (p. 528). Literally, the statement of the problem for this literature review is the words “can” and “is” in the quoted statements above. Does vocabulary instruction improve comprehension? Research Question Positively affecting reading comprehension and increasing vocabulary are significant teacher tasks. However, being able to affect how students retain and then transfer these skills in VOCABULARY, COMPREHENSION, RETENTION 5 the future must also be considered. Martin-Chang, Levy, and O’Neil (2007) state, “Successful reading instruction entails not only acquiring new words but also remembering them after training has finished and accessing their word-specific representations when they are encountered in new text” ( p. 37). While there appears to be a relationship between vocabulary, reading comprehension, and the need for students to retain and apply these skills in future reading tasks, one wonders the degree to which these are related. The research question guiding this review of literature was: What is the relationship between vocabulary instruction, reading comprehension and student retention? Definition of Terms cloze procedure “a multifunctional strategy, which can be used for reading diagnosis and reading comprehension instruction” where students “fill in a missing word in a piece of text or a familiar language pattern” (Chatel, 2001, p. 3) comprehension – “understanding written text” (Tannenbaum, Torgesen, & Wagner, 2006, p. 381) context – “the language that surrounds a given word or phrase” (Moats, 2005, p. 66) phonology – “rules system within a language by which phonemes [individual speech sounds] can be sequenced, combined, and pronounced to make words” (Moats, 2005, p. 68) semantic mapping – “a categorical structuring of information in graphic form” (Johnson, Pittelman, Heimlich, 1986, p. 779) vocabulary – “words that a reader recognizes in print” and “learning meanings of new words” (Beck, McKeown, Kucan, 2008, p.1) VOCABULARY, COMPREHENSION, RETENTION 6 Chapter II: Review of the Literature This review of literature will describe research on vocabulary, vocabulary instruction, reading comprehension, and student retention. Vocabulary Nash and Snowling (2006) describe vocabulary as “the knowledge of words and their meanings” (p. 336). While Sheehan (2002) states vocabulary is “the ability to understand and use words to acquire and convey meaning” (Vocabulary, para. 1).Vocabulary is an essential element of reading instruction. Clearly, vocabulary and comprehension are closely connected skills. Each skill is imperative to reading achievement, yet one relies heavily on the other. This intricate relationship has been documented by many researchers. “Vocabulary development is both an outcome of comprehension and a precursor to it, with word meanings making up as much as 70-80% of comprehension” (Bromley, 2002, p. 528). Harmon (2002) notes, “Many students continue to struggle with comprehension because of limited vocabulary knowledge and ineffective strategies” (p. 606). While many researchers have examined the correlation between vocabulary and comprehension, other researchers have described how a larger vocabulary contributes to other areas of school success. Manzo, Manzo, and Thomas (2006) concluded “word learning can improve the capacity to learn” and “a rich vocabulary increases comprehension and, therefore, most all learning” (p. 615). Simply stated, Lubliner and Smetana (2005) declared, “Children with larger vocabularies find reading easier, read more widely, and do better in school” (p. 163). Students with larger vocabularies usually articulate responses to questions and ask better VOCABULARY, COMPREHENSION, RETENTION 7 questions than their peers with limited vocabularies. Vocabulary can not only contribute to achievements in language arts classes, but to other areas of study as well. Reading researchers emphasize the importance for teachers to utilize an effective vocabulary instruction method to improve comprehension as early as possible. Jenkins, Matlock, and Slocum (1989) stress how students can be negatively affected by poor reading comprehension. “With each year of schooling, texts take on a larger role in instruction, and factors that may inhibit comprehension of these texts, such as a lack of vocabulary knowledge, can be expected to have increasingly detrimental effects on achievement” (p. 217). Recognizing and understanding more words will increase the likelihood that students will comprehend what they are reading and therefore perform better in school. Although it appears students can benefit from teachers who include vocabulary instruction in their lessons; instructional methods of effective vocabulary instruction remain elusive. Bromley (2007) states, “Many teachers know they need to do a better job teaching vocabulary to students who find reading difficult” (p. 528). However, selecting the most appropriate method of vocabulary instruction is a difficult task. Lubliner and Smetana (2005) describe this difficulty in their work, “The ultimate challenge of a vocabulary intervention is not merely to teach a set of words or skills, but to positively affect reading comprehension” (p. 189). Methods of vocabulary instruction vary greatly. Three of the most researched instructional methods, contextual, semantic mapping, and combination instructional approaches are the basis of this literature review. Context and Comprehension Contextual vocabulary instruction involves teaching students to use the context, or words appearing directly before and after, of a sentence to determine a word’s meaning. Students can VOCABULARY, COMPREHENSION, RETENTION 8 use the contextual vocabulary method during independent reading as well as during teacher-led vocabulary lessons. “Learning from context is an important avenue of vocabulary growth and it deserves attention and practice in the classroom” (Nagy, 1988, p. 7). Two types of contextual methods of vocabulary instruction are pedagogical and natural. Each method focuses on teaching students to use context to determine meaning. The first contextual method is called the pedagogical or instructional method. Teachers and/or authors of basal reading series write sentences specifically to teach the meaning of the vocabulary words within context. This contextual method is called the pedagogical or instructional method. One example of an instructional context sentence appears in work by Herman and Dole (1988). “Mastodons became extinct years ago when the last one died” (p. 47). Students can use the information from the sentence to determine extinct’s definition. The second approach, natural contextual method, uses sentences containing the vocabulary words; however the sentences were written to communicate information rather than teach word meanings. An example of a natural context sentence is “The cobbler mended my favorite red sandals.” Because this sentence does not tell specifics about a cobbler, students must infer the meaning from the rest of the sentence. Teachers should carefully monitor student inferences when using this method. Based on natural context, students’ inferences about a word’s meaning could be wrong. Nagy used the following example to illustrate this possibility: “Although Mary was thin, her sister was obese”. Students may infer that obese means “normal,” “unconcerned,” or “not jealous” (p. 7). He also noted that this example relied on contrast and other less informative contexts “would allow an even wider range of possible substitutions” (p. 7). Knowing the possibility for student errors while using this method is important for teachers to understand and examine. VOCABULARY, COMPREHENSION, RETENTION 9 Teachers implement contextual vocabulary instruction by training students to use clues in the sentence. Nash & Snowling (2006) described the process as: “Strategies for teaching children how to derive meaning from context focus on using pieces of information (cues) in the context to infer the meanings of target words” (p.337). By showing students how to recognize these clues, students can then use this strategy during independent reading. The contextual methods do not require any specific materials or specialized training for the teacher and can be used on as many words as deemed necessary by the teacher. In the section that follows, I will review three studies conducted to examine contextual strategies in comparison with other instructional strategies and their potential to improve vocabulary, comprehension, and student retention. Comparison of Definition and Context Instruction Nash and Snowling (2006) asked which of two methods of vocabulary instruction was more effective in increasing vocabulary knowledge in students with poor existing vocabulary knowledge. Their purpose was to determine if one method of vocabulary instruction also caused an increase of students’ reading comprehension scores. The two vocabulary instruction methods were a definition program, where students were given the definitions of words and then wrote these words on paper, and a context program, where students were given a few sentences for each word in context and then discussed context cues. This experimental study began with 71 participants (41 females and 30 males) from a primary school in York, England. Students were screened using tests of receptive vocabulary, narrative skills, and reading. After the screening, 24 children (ten females and 14 males) were determined to be the bottom third of the sample and were then placed into one of the intervention groups. “Children were ranked and assigned in closely matched pairs to one of the two teaching VOCABULARY, COMPREHENSION, RETENTION 10 programs” (p. 339).To ensure only the method of instruction varied between groups, several factors were carefully controlled. Both groups had the same instructor, amount of time per lesson, days of instruction, vocabulary words, and number of students. Hypotheses tested were: student instruction will show a “difference in favour [sic] of the context group in terms of expressive but not receptive vocabulary score” (p. 339) when compared to the definitions method and “reading comprehension of the passage containing taught words should be significantly better at post-test for the context group than the definitions group” (p. 339). Students from each intervention group were given two vocabulary post-tests, one immediately after teaching and then three months later.