**5. Measures**

All students were assessed by the school's reading specialists prior to the beginning of the treatment and again in January at the end of the treatment using the Benchmark Assessment System (BAS) [49]. The BAS was chosen as it was the assessment system normally used by the school to measure students' reading progress. The BAS is an individual formative reading assessment in which students are asked to orally read and respond, in a comprehension conversation with the examiner, to a series of graded texts. Data are gathered on students' word recognition accuracy, fluency, and reading comprehension. The examiner uses the accumulated data to determine each student's instructional

and independent reading levels. Reading levels are specified in alphabetical levels (Levels A through J for grades K-1). The BAS had been used in this school for more than five consecutive years.

A published study of reliability and validity reports that the texts used in the BAS are progressively more difficult and that approximately 80% of K-2 students' reading performance of the graded texts followed the sequential hierarchical order. According to the Field Study of the Reliability and Validity of the Fountas and Pinnell Benchmark Assessment Systems 1 and 2 test–retest reliability for all BAS (0.94) levels ranges from 0.93 to 0.97. Convergent reliability indicated the BAS was highly predictive of Reading Recovery Assessments (0.94) and moderately predictive of the Slosson Word Test (0.69). The same study also reported a strong correlation (r > 0.91) between the BAS text levels and texts in the Reading Recovery Text Level Assessments [50]. Overall, the BAS is reported to be a valid and reliable means for assessing students' reading levels.
