A new measure of reading comprehension, the Diagnostic Assessment of Reading Comprehension (DARC), designed to reflect central comprehension processes while minimizing decoding and language demands, was pilot tested. We conducted three pilot studies to assess the DARC's feasibility, reliability, comparability across Spanish and English, developmental sensitivity, and relation to standardized measures. The first study, carried out with 16 secondthrough sixth-grade English language learners, showed that the DARC items were at the appropriate reading level. The second pilot study, with 28 native Spanish-speaking fourth graders who had scored poorly on the Woodcock-Johnson Language Proficiency Reading Passages subtest, revealed a range of scores on the DARC, that yesno answers were valid indicators of respondents' thinking, and that the Spanish and English versions of the DARC were comparable. The third study, carried out with 521 Spanish-speaking students in kindergarten through grade 3, confirmed that different comprehension processes assessed by the DARC (text memory, text inferencing, background knowledge, and knowledge integration) could be measured independently, and that DARC scores were less strongly related to word reading than Woodcock-Johnson comprehension scores. By minimizing the need for high levels of English oral proficiency or decoding ability, the DARC has the potential to reflect the central comprehension processes of secondlanguage readers of English more effectively than other measures.The purpose of this article is to consider the challenges of assessing comprehension in second-language (L2) readers and to report on three studies conducted to develop and validate a new measure of reading comprehension called the Diagnostic Assessment of Reading Comprehension (DARC). The DARC, based on the assessment first de- Even more important, there is little basis for deciding the relative importance of these factors in determining poor comprehension outcomes for individual children or groups of children. Knowing how each factor contributes to comprehension could help in designing optimally differentiated comprehension instruction. In other words, if a group of children comprehends poorly because of failure to draw appropriate inferences, then attention to strategies for constructing inferences makes instructional sense. However, if children show normal ability to form inferences but lack relevant vocabulary knowledge, then focusing instruction on forming inferences is a waste of time. The ultimate purpose of the DARC is to provide teachers with a better basis for adapting instruction to individual students' needs by helping to identify subgroups of struggling comprehenders.
Reasons Children Fail at ComprehensionMany children score poorly on comprehension assessments because their word reading is inaccurate (e.g., Adams, 1990;Gough & Tunmer, 1986;Vellutino, 1979Vellutino, , 1987; children growing up in poverty often fall into this group (National Research Council, 1998). Some children who read accu...