A primary-grade-level instrument was developed to measure thinking prerequisites to reading comprehension. Levels of responses are identified as either perceptual or conceptual; the ability to synthesize concepts from several sources and make generalizations is also measured. Analyses of partial construct validity, of cross-form reliability, and of cross-reader reliability are discussed, using data from fifth-grade students. Scoring instructions and test items for Form A of the test are included as an appendix. (AA)