Testing 101: How to Understand and Use NCE and Stanine Scores
I think very few of us are what you call “numbers people.” Most people when they finished algebra 1 or algebra 2 in high school, or college math for that matter, had no intention of ever returning to it “just for fun.” Why? Because it lacked relevance and usefulness to their life. NCE (normal curve equivalent) scores also lack significance to most of us. But, inasmuch as they appear on your student’s test report, here are a few facts you still might want to know about them.
Normal Curve Equivalent Follows the National Percentile
When reviewing your achievement test reports, the NCE score follows the National Percentile score (NP) score as you read across the page. These scores are represented on a scale from 1 to 99. 1 is the lowest score; 99 is the highest. When an NCE score is 50, the NP will also be 50 for the same test. When the NP score drops below 50, the NCE score will always be a little higher. When the NP score is above 50, the NCE score will be always be a little lower. Once again it will be helpful for you to reference our sample report (click here to view) to see this.
On the sample report, the NP score for Total Score (sometimes identified as the Battery Total) is 53. As expected, the NCE score for the Total Score is slightly lower at 51. Looking at the NP score for Reading, we find it to be 34. The corresponding NCE score is 41, higher than the NP score as expected. Looking at the NP score for Language, we find it to be 56. The corresponding NCE score is 53 which again, is lower than the NP score as expected.
Using NCE Scores to Compare Student Performance
Another fact about NCE scores is that the difference between successive scores is the same throughout the scale. Because this is true, NCE scores may be averaged which in turn allows scores to be compared to each other if you’re into that sort of thing.
Next to the NCE scores on the test report are the Stanine scores (S9). Stanines are always expressed as single digits, 1 to 9. They can easily be used to compare student performance but are less precise than percentile ranks because they are single digits.
Now a tidbit of information regarding stanines. This score gets its name from the fact that it is a standard score linked to a scale of nine units. The chart below shows how Stanine Scores are related to National Percentile Ranks. The chart also shows the percentage of students in a given population related to each stanine.
Comparison of Stanines and Percentiles
| Stanines | Approximate Percentiles | Percentage of Students |
| 9 Highest Level | 96-99 | 4% |
| 8 High Level | 90-95 | 7% |
| 7 Well Above Average | 78-89 | 12% |
| 6 Slightly Above Average | 60-77 | 17% |
| 5 Average | 41-59 | 20 % |
| 4 Slightly Below Average | 23-40 | 17% |
| 3 Well Below Average | 11-22 | 12% |
| 2 Low Level | 5-10 | 7% |
| 1 Lowest Level | 1-4 | 4% |
Take a look again at the sample report and look at the scores for Reading. This student’s NP was 34 placing him or her in the slightly-below-average range of 23-40. The corresponding NCE score is 41, higher than the percentile as expected. The corresponding S9 score is a 4.
Following the S9 score is the grade equivalent score which is a 4.3. This represents fourth grade, third month. The student taking this test was being compared to other students ending fifth grade as indicated at the top of the test report.
In light of this grade equivalent score, should the parent be concerned? I’ll let you know in the next article.
- Our test dates for Washington are now available, including an upcoming test on Thursday, April 19th at the Firmly Planted Resource Center.
- Click here to view all Washington test dates.
