In fact, if items that pose challenges to nonmonolingual-home learners are characterized by more cognitive academic language structures than other items, this would also support the need to differentiate between academic language and basic interpersonal language structures. Second, in terms of theory building, a closer look at the linguistic properties of the items used on reading fluency tests might aid the understanding of what makes reading difficult for nonmonolingual-home learners.

This would have two important implications: First, from a psychometric perspective, such a test would not be equally valid for students with monolingual versus nonmonolingual language backgrounds, and such a finding would have consequences for the use of this test in all diagnostic settings. If this were the case, the test score would reflect not only basic reading skills but also certain linguistic competencies within this group. In this study, we sought to determine whether students with a non-German home language have problems understanding some items on reading fluency tests due to certain linguistic characteristics of the items. However, little information has been provided about the error rates of most of these tests, and not many studies have scrutinized the differential error rates across different groups of test-takers. If the error rate is very low and does not vary across different groups of test-takers, the items can be expected to pose no problems for readers’ understanding.

The so-called error rate can be used as an indicator that reading speed and accuracy are really the main sources of variation. Reading fluency tests are characterized by easy-to-understand content and language so that reading time is not affected by specific knowledge (e.g., cultural information), unknown vocabulary, or unfamiliar or complex syntactic constructions. The main difference between silent and oral reading is that speech production (voice articulation) speed is not measured by tests of silent reading fluency. Given that in silent reading, the prosodic indicators are measured through the reader’s “inner voice” (Féry, 2016), oral and silent reading fluency tests measure the same abilities to a large extent (Bar-Kochva, 2013 Share, 2008). Fluency tests measure “the ability to read a text quickly, accurately, and with proper expression” (National Institute of Child Health and Human Development, 2000, Chapter 3, p. There are three general types of widely used reading tests: (a) decoding/accuracy tests, (b) reading comprehension tests such as those applied in the Programme for International Student Assessment (PISA Organisation for Economic Co-operation & Development-OECD, 2016), and (c) oral/silent reading fluency tests.

Test of silent reading efficiency