NNAT3 Score Interpretation 3 — Questions and Answers
Question 1: A student's NNAT3 raw score increased by 4 points from one testing to the next. What is the most accurate interpretation?
- The student's ability definitely improved
- The gain may reflect measurement error rather than true growth (Correct answer)
- The student's NAI increased by exactly 4 points
- The percentile rank rose by 4 points
Correct answer: The gain may reflect measurement error rather than true growth
Raw score changes can fall within the test's standard error of measurement and may not reflect genuine ability change.
Question 2: If two students the same age earn the same NNAT3 NAI score but different raw scores, what explains the discrepancy?
- One student cheated
- Different test forms have different numbers of items by level (Correct answer)
- The NAI is calculated incorrectly
- Percentile ranks were applied to raw scores
Correct answer: Different test forms have different numbers of items by level
NNAT3 has multiple levels with different item counts, so the same NAI can correspond to different raw scores across levels.
Question 3: A parent asks why their child's NNAT3 score is described as 'above average' even though the child got several questions wrong. What is the best explanation?
- Scores are curved to make everyone look better
- Performance is compared to age peers, not to a perfect score (Correct answer)
- Wrong answers are not counted against the student
- The test only counts easy items
Correct answer: Performance is compared to age peers, not to a perfect score
The NNAT3 is norm-referenced, so a score is interpreted relative to how other same-age students perform, not against a 100% benchmark.
Question 4: Which NNAT3 score is the most stable across repeated testing sessions?
- Raw score
- Percentile rank
- Naglieri Ability Index (NAI) (Correct answer)
- Number of omitted items
Correct answer: Naglieri Ability Index (NAI)
The NAI, as a standardized age-adjusted score, shows greater stability than raw scores because it accounts for measurement properties of the test.
Question 5: An NNAT3 score report shows a 90% confidence interval of 102–118 for an NAI of 110. What does this mean?
- The student will definitely score between 102 and 118 if retested
- There is a 90% chance the student's true score falls between 102 and 118 (Correct answer)
- 10% of students score between 102 and 118
- The student scored 90% correct on the test
Correct answer: There is a 90% chance the student's true score falls between 102 and 118
A 90% confidence interval means that if testing were repeated many times, 90% of those intervals would contain the student's true score.
Question 6: A student scores at the 95th percentile on the NNAT3. Which stanine does this most likely correspond to?
- Stanine 5
- Stanine 7
- Stanine 9 (Correct answer)
- Stanine 3
Correct answer: Stanine 9
The 95th percentile falls in stanine 9, the highest stanine band, representing approximately the top 4% of scores.
Question 7: Why does the NNAT3 use age-based norms rather than grade-based norms for its primary scores?
- Grade-based norms are more expensive to collect
- Cognitive ability develops with age, not grade level (Correct answer)
- Students within a grade are always the same age
- Age norms are required by federal law
Correct answer: Cognitive ability develops with age, not grade level
Nonverbal reasoning ability is tied to cognitive development, which correlates with age; age norms provide the most accurate comparison for ability testing.
NNAT3 Score Interpretation 3
A student's NNAT3 raw score increased by 4 points from one testing to the next.
What is the most accurate interpretation?