To determine whether mastery of one reading comprehension task is a prerequisite to mastery of two or more reading comprehension tasks, a study examined the prerequisite relations existing in the item responses elicited from a sample of sixth grade students who took the Iowa Tests of Basic Skills, Form G, Level 12 reading comprehension test. Test items for 86 sixth graders enrolled in a small midwestern municipal school system were used for the study. To identify prerequisite relations (defined here as "a capability of prior learning which is incorporated into new learning"), item responses were submitted to an ordering-theoretic approach with a zero level tolerance for disconfirmatory response patterns. The identified prerequisite relations were submitted to a statistical test which used unit normal deviate approximation to determine whether the prerequisite relationships occurred by chance. Significant relationships were found to underlie the data, but no meaningful pattern in the results could be found when using the classes of skills objectives (i.e. facts, inferences, and generalizations) to explain the results. No meaningful pattern was found when analyzing data with Meyer's five rhetorical relationships; however, B. J. F. Meyer's three distinct levels of content structure proved helpful in explaining the results. Analysis indicated that by using ordering theoretic methods, reading teachers can determine what reading comprehension tasks comprise new learning and thus tailor the following year's instruction vis-a-vis prerequisite relations. One table is included. Appendixes consist of: reading comprehension tasks; table of notation for response patterns for two dichotomously scored items; and unit normal deviate approximation formula. (MM)