Technical Manual - Renaissance Learning

ValidityRelationship of STAR Early Literacy Scores to Age and School GradeAs was true of the non-adaptive Calibration Study data, adaptive test scores fromthe Validation Study increased systematically from pre-kindergarten throughgrade 3. The standard deviation statistics show that score variability was similarfrom pre-kindergarten through grade 1, but less variable in grades 2 and 3.The Validation Study took place during April and May, the seventh and eighthmonths of the school year. The data in Table 20 therefore represent ages andScaled Scores about three-quarters of the way through the school year.Figure 4 illustrates the relationship of Scaled Scores to school grade in a morecomplete way. The figure consists of curves that display the percentile equivalentsof Scaled Scores separately for each grade from pre-kindergarten through grade 3.The point of showing these figures together is to emphasize that 1) scoredistributions in these five grades are quite different from one another; and 2)grade-to-grade differences are largest at the lowest grades, and becomeconsiderably smaller by grade 3, by which time most students can be expected tohave mastered early literacy skills.Figure 4:STAR Early Literacy Scaled Score Percentiles by Grade as Observedin the US Sample in the Validation StudyFigure 5 displays average STAR Early Literacy Scaled Scores for 11 age groups ofstudents participating in the Validation Study. Each age group spans a six-monthage range; the youngest group ranged from 4.5 to 5.0 years old on the date of theSTAR Early Literacy assessment; the oldest group ranged from 9.5 to 10 years old.As the figure shows, on average, STAR Early Literacy Scaled Scores increaseddirectly with students’ ages from below 5 to above 9 years old. A small decreaseoccurred for the oldest age group; this decrease probably reflects the performanceof a disproportionate number of low-ability students in the oldest age group.STAR Early LiteracyTechnical Manual57