Washback refers to the influence of a test on teaching and learning, arising both directly and through mediating factors. The washback of the Common Test for University Admissions (the Common Test) can arise not only from its direct impact but also from mediating factors. One such mediating factor in relation to the English section of the Common Test is the extent to which commercially available mock examinations accurately reflect the actual test. Against this background, the present study analyzes the English reading sections of mock examinations produced by major preparatory schools (yobiko), aiming to clarify how these mock tests mediate the washback effect.Yobiko generally produce two types of mock examinations. The first type is the “workbook,” which compiles past mock examinations and is typically released early in the test preparation period (e.g., in the spring), containing multiple test forms. The second type is the “final-prep pack,” a comprehensive package of mock tests designed to simulate the actual Common Test closely. Because these packs are sold and used immediately before the examination and often contain only a single test set for each subject, they are likely to have greater washback intensity than workbooks.To examine how closely these final-prep packs reflect the actual test, this study compared the vocabulary level and readability of the Common Test English Reading test with those of final-prep packs published by three major yobiko. The passages from each test were converted into plain text to compute vocabulary and readability indices. The results showed no statistically significant difference in vocabulary levels between the actual test and the commercially available packs. However, readability indices indicated that the final-prep packs were significantly more difficult than the actual test. This gap suggests a potential source of negative washback, as it may lead examinees to perceive the Common Test as more difficult than it actually is, potentially affecting test-takers’ test preparation.

Debates continue in Japan over replacingthe National Center Test for University Admissions (hereafter, the Center Test)in the English sections of university entrance exams. Although the use ofexternal tests—such as the EIKEN Test and TOEFL iBT—has been considered,retrospective evaluations of the Center Test’s washback effects (i.e., theinfluence of testing on teaching and learning) remain scarce. In discussionssurrounding the introduction of the new Common Test in 2025 or the adoption ofexternal tests, it is essential to first examine the longstanding Center Test.Such analysis can help uncover underlying mechanisms of washback in the currentcontext of English education in Japan.Despite the Center Test’s widespreadinfluence, the role of shadow education—particularly private preparatoryschools (yobiko) and cram schools (juku)—in mediating its effects has receivedlimited scholarly attention. Notably, these institutions not only provideinstruction but also design and administer mock tests. Students use thesepractice tests, which closely mirror the format and content of the officialexam, to assess their performance and make informed decisions about universityapplications. However, the extent to which yobiko-developed mock tests differfrom the official Center Test has not been systematically investigated. Thesedifferences may exert indirect effects on learners through washback, thuswarranting further examination.This study investigates the washbackeffects of the Center Test’s English section, focusing on its influence onteaching and learning. Specifically, it compares official test items from the2018 Center Test with three sets of mock tests produced by major yobikoinstitutions to explore the potential indirect impact of shadow education.The findings are as follows: In thetext-based analysis, readability indices revealed that while the mock testswere more difficult than the official test in Reading Section Part 6, overalldifficulty levels were comparable. Vocabulary indices indicated that theofficial test was generally easier than the mock tests. In the coding analysis,the reading skills assessed were largely consistent between the official andmock tests. By focusing on one dimension of the Center Test’s washback effect,this study sheds light on how large-scale standardized tests in Japan shapeteaching and learning.

The washbackeffect, which refers to the impact of tests on teaching and learning, is asignificant topic in language testing. However, existing research on thewashback effect has primarily focused on large-scale tests, with limitedattention given to the impact of small-scale tests in classroom settings. Therefore,this study investigates the effects of quizzes in Japanese university TOEIC Listening& Reading Test (hereafter TOEIC) courses.One of thecharacteristics of the impact of quizzes in university TOEIC courses, withinthe framework of washback studies, is the dual influence observed—both from theTOEIC on learners and from quizzes within the context of TOEIC andlearners. While previous studies have addressed washback studies of the TOEIC, no studies have not discussed simultaneously both the direct impact ofin-class TOEIC quizzes, situated between TOEIC and learners, and the indirectimpact of large-scale tests like the TOEIC, which underlies the direct impactof the TOEIC. Given the context-specific nature of the washback effect, it isimperative first to comprehend the learning environment in which quizzes areadministered in university TOEIC classes.This studyfocuses on quizzes in Japanese university TOEIC classes and identifies thefactors mediating classroom quizzes’ washback effect. The participants wereprivate university students in the Kanto area in Japan enrolled in TOEICcourses where vocabulary and grammar quizzes were conducted. Many studentsparticipated in a two-semester TOEIC course for one year, taking grammar orvocabulary quizzes every 10 weeks. The format of the quizzes involved multiplechoice questions for grammar tests and matching exercises for vocabulary tests,respectively. This study employed an open-ended questionnaire and conductedinterviews with a participant to explore the factors mediated by the quizzesand their surroundings in TOEIC courses. The questionnaire content, interviewquestions, and subsequent analysis were informed by the categorization offactors in the washback effect established in previous studies, includingspecificity, intensity, length, intentionality, and value.The study’sfindings suggest potential mediating factors for future investigations of TOEICquiz washback, such as the weekly study workload, familiarity with the quizformat, and the sequence of experiencing vocabulary and grammar quizzes. This studyprovides a way to conduct future studies by capturing the varying degrees ofimpact of both TOEIC quizzes and the TOEIC.

As of 2022, external tests are used inparallel with the in-house tests developed individually by each university for Englishlanguage university entrance examinations in Japan. However, for universitiesto select and use appropriate external tests, it is desirable to understand thepurpose of the test development and construct of each external test used in conjunctionwith the in-house test, and to compare and contrast them with their in-house test.At the same time, empirically understanding the test contents is the first steptoward predicting the washback effects of using each test, i.e., the impact ofthe tests on teaching and/or learning. Therefore, this study conducted a testcontent analysis of external tests used at several universities. The analysiswas conducted using the framework of language assessment theory.