the event in order to inform an appropriate response. How much time did the student take to complete the test? How much negative growth was actually observed? Have living conditions changed at home? Is the student suffering from poor attitude, anxiety, or motivation issues? Have there been changes in the student’s attendance or in classroom instruction? Is the data consistent with other classroom data? These questions are provided as a resource at the end of this article and are encouraged to be used when examining students’ scores. Gathering information around these questions can help inform our response, which generally would involve a combination of the following two actions:
1. Determining the need to retest the student (critical if the drop is more than 10 RIT)
2. Determining the need to adjust instruction (utilizing DesCartes)
PUTTING STUDENT GROWTH IN CONTEXT
There can be many reasons for a drop in a student’s score, but one important factor that must be considered is something known as standard error of measurement. This statistical term is used to indicate the error in a reported RIT score, providing a possible range of expected scores for the student generally known as a RIT Range.
Typically, this approximates to about plus or minus three RIT on any given test, so a RIT score of 200 would likely yield a RIT Range of 197-203. Let’s look at the considerations of this a bit further.
Spotlight: Standard Error of Measurement and RIT Ranges
Consider a student with the following test data:
Fall RIT Score: 210 +/- 3 RIT Fall RIT Range: 207-213
Winter RIT Score: 203 +/- 3 RIT Winter RIT Range: 200-206
How much negative growth is seen for this student between fall and winter testing?
Is it 1, 7, or 13 RIT? The truth is that the amount of negative growth could be any of these amounts. The RIT Ranges imply that the spread of accurate scores could have fallen from an extreme high of 213 in the fall to an extreme low of 200 in the winter. They also could have minimally fallen from 207 in the fall to 206 in the winter or any combination within the parameters of the RIT Ranges. All that can truly be ascertained is that the score has fallen. Which leads to the larger question, what is the significance of this change in RIT?
As the spotlight above shows, differences in RIT may not always be what they appear. Of course this same reasoning holds true for any perceived gains, which is why it is best to look at the impact of any change in RIT from an instructional viewpoint. When we insert either of the RIT scores from the above example into DesCartes (207 or 203) we find that the student is still performing in the same RIT Band of 201-210. Fundamental to the use of DesCartes is the notion that the learning level of the student will remain the same throughout the ten point RIT Band. This holds true regardless of any perceived gains or losses between test sessions. Perhaps this student needs more practice, or alternative methods of instruction, but the content of the RIT Band is still the appropriate learning level for the student.
When first referencing DesCartes it is common to focus solely on the RIT score. While this is appropriate, the adjacent RIT Bands in DesCartes may contain useful instructional skills which relate to the student’s RIT Range. You may remember that the three adjacent RIT Bands in DesCartes represent skills which a student may answer correctly 25%, 50%, and 75% of the time respectively, with the student’s RIT score falling into the center RIT Band. Though it is important to utilize the student’s primary RIT Band during instruction, the skills in the adjacent RIT Bands should not be ignored.
DEALING WITH NEGATIVE GROWTH
It is well known that instructional decisions should not be based entirely on one data point, but in situations where negative growth pulls a student’s RIT score into a lower RIT Band this is especially true. In these instances it is essential that we rely on other sources of data to verify the child’s instructional level. By reviewing classroom assignments and assessments we may be able to dete