IDAT Evaluation and Results 2 — Questions and Answers
Question 1: On the IDAT, which score report component helps admissions committees distinguish between students who performed similarly on the overall exam?
- Subscale scores by domain (Correct answer)
- A single composite percentile
- The test date only
- The number of unanswered items
Correct answer: Subscale scores by domain
Subscale scores break performance into specific domains, allowing committees to differentiate candidates with similar total scores.
Question 2: A student's IDAT result shows a stanine of 5. What does this indicate about their performance?
- Performance is in the average range (Correct answer)
- Performance is in the bottom 10%
- Performance is in the top 10%
- The score is invalid and must be retested
Correct answer: Performance is in the average range
Stanine 5 is the middle band (stanines 4–6 are average), indicating typical performance relative to the norm group.
Question 3: Which of the following BEST describes a norm-referenced interpretation of IDAT results?
- Comparing a student's score to those of a representative peer group (Correct answer)
- Comparing a student's score to a fixed mastery standard
- Reporting the raw number of correct answers
- Measuring growth from a prior administration
Correct answer: Comparing a student's score to those of a representative peer group
Norm-referenced interpretation ranks a test-taker's performance relative to a norming sample rather than a fixed cut score.
Question 4: An IDAT candidate scored at the 60th percentile. Which statement is accurate?
- The candidate scored higher than 60% of the norming group (Correct answer)
- The candidate answered 60% of questions correctly
- The candidate is in the top 40% of all possible scores
- The candidate met the minimum admissions threshold
Correct answer: The candidate scored higher than 60% of the norming group
A percentile rank of 60 means the student outperformed 60% of the reference group, not that they got 60% of items correct.
Question 5: Why might an IDAT score report include a confidence interval around the obtained score?
- To reflect the inherent measurement error in any standardized test (Correct answer)
- To indicate the range of acceptable passing scores
- To show the range of dates on which the exam can be retaken
- To list the number of questions in each section
Correct answer: To reflect the inherent measurement error in any standardized test
Confidence intervals acknowledge standard error of measurement, showing the range within which the true score likely falls.
Question 6: When evaluating IDAT diagnostic results for instructional planning, which action is most appropriate?
- Target instruction toward domains with the lowest subscale scores (Correct answer)
- Focus only on the total composite score for all decisions
- Retest all students before any intervention
- Ignore scores below the 25th percentile as unreliable
Correct answer: Target instruction toward domains with the lowest subscale scores
Subscale scores identify specific weak areas, making them the most useful guide for targeted instructional intervention.
Question 7: Which factor would most likely REDUCE the validity of interpreting IDAT results for a specific student?
- The student took the exam under non-standardized conditions (Correct answer)
- The student's first language is the same as the test language
- The student completed all sections within the allotted time
- The student had prior familiarity with the test format
Correct answer: The student took the exam under non-standardized conditions
Non-standardized conditions (e.g., extended time not approved, distractions) compromise the comparability and validity of scores.
IDAT Evaluation and Results 2
On the IDAT, which score report component helps admissions committees distinguish between students who performed similarly on the overall exam?