5.6 Norm-Referenced and Criterion-Referenced Assessment
Key Takeaways
Norm-referenced tests compare a student to a norming sample; criterion-referenced tests compare performance to a fixed standard.
Percentiles, stanines, and grade equivalents are norm-referenced score types; mastery levels and cut scores are criterion-referenced.
Norm-referenced results are invalid for English learners when the norming sample excluded them.
Criterion-referenced results tell a teacher which specific skills were and were not mastered, which is what instructional planning requires.
Grade-equivalent scores are the most misinterpreted score type and should never be read as a recommended placement level.
5.6 Norm-Referenced and Criterion-Referenced Assessment
The ETS content outline names this distinction explicitly: the candidate "knows the difference between norm-referenced and criterion-referenced assessments and how they are used with ELs," and recognizes both the consequences of norm-referenced comparison for English learners and the instructional utility of criterion-referenced information. The distinction is not about the test items — it is about what the score is compared to.
1. The Core Contrast
| Norm-referenced (NRT) | Criterion-referenced (CRT) | |
|---|---|---|
| Answers the question | "How does this student compare to other students?" | "What can this student actually do?" |
| Reference point | A norming sample of test-takers | A fixed standard, objective, or cut score |
| Score types | Percentile rank, stanine, normal curve equivalent, grade equivalent, standard score | Percent correct, mastery/non-mastery, performance level, proficiency-level descriptor |
| Item design | Items chosen to spread scores out; very easy and very hard items are discarded | Items chosen to represent the standard; everyone can, in principle, score 100% |
| Distribution | Designed to produce a bell curve; half of all students are below average by construction | No fixed distribution; all students could reach mastery |
| Primary uses | Screening, program eligibility, comparison to a population | Instructional planning, progress monitoring, grading, standards accountability |
| Examples | Cognitive ability batteries; nationally normed achievement tests | Unit tests, state standards assessments, ELP performance-level determinations, rubric-scored performance tasks |
The bell-curve consequence
A norm-referenced test is engineered so that scores spread. That means "below average" is a statistical position, not a diagnosis. Fifty percent of the norming population scores below the median by design. A parent told their child is "below the 50th percentile" has been given a ranking, not a description of what the child knows.
2. Decoding Norm-Referenced Score Types
| Score type | What it means | Common misreading |
|---|---|---|
| Percentile rank | Percent of the norming group this student outscored (e.g., 62nd percentile = outscored 62%) | Mistaken for percent correct |
| Stanine | Nine-point band; 4-6 is the average range | Treated as a fine-grained measure |
| Normal curve equivalent (NCE) | Percentile rescaled to equal intervals so scores can be averaged | Confused with percentile |
| Standard score | Distance from the mean in standard-deviation units (often mean 100, SD 15) | Read as a percentage |
| Grade equivalent (GE) | The grade level at which this raw score would be the median | The most dangerous score type on any report |
The grade-equivalent trap
A 4th grader who earns a grade equivalent of 7.2 has not demonstrated 7th-grade skills. It means her raw score equals the median raw score of 7th graders on the 4th-grade test — a test containing no 7th-grade content. Grade equivalents are extrapolated, unequal-interval estimates and should never be used to set placement, select texts, or write goals. The same logic runs the other way: a 6th-grade EL with a GE of 2.4 has not been shown to "read like a 2nd grader."
3. Why Norm-Referenced Tests Distort English Learner Performance
This is the point the exam presses hardest, and it follows directly from the norming-sample bias discussed in Section 5.2.
- The comparison group is inappropriate. If the norming sample consisted overwhelmingly of native English speakers, then comparing a developing multilingual learner to it produces a ranking against a population the student is not a member of. The resulting percentile measures English proficiency as much as the target construct.
- Language becomes construct-irrelevant variance. On a nationally normed science or mathematics test delivered in English, an EL's score confounds content knowledge with English reading ability (Section 5.3).
- Consequences compound. Low norm-referenced scores drive placement into remedial tracks, exclusion from gifted screening (Section 4.7), and over-referral to special education (Section 5.5) — outcomes documented as disproportionality, not as accurate measurement.
- Cultural content bias. Items presuppose U.S.-specific background knowledge that is unrelated to the skill being measured.
Legitimate uses remain. Norm-referenced data is not useless: it can flag a student for further examination, and it is required for some eligibility determinations. The rule is that a norm-referenced score alone may never drive a high-stakes decision about an English learner. It must be triangulated with criterion-referenced data, native-language performance, work samples, and observation over time.
4. Why Criterion-Referenced Data Drives Instruction
Criterion-referenced results answer the question a teacher actually needs answered on Monday morning.
| Report says | Instructional value |
|---|---|
| "38th percentile in reading" | None. It ranks the student; it names no skill |
| "Mastered main idea and sequencing; not yet mastered inference from context clues" | Directly actionable — the next lesson writes itself |
This is why progress monitoring, rubric-scored performance tasks, and standards-based grading are criterion-referenced by design (Section 5.5), and why English language proficiency assessments report performance-level descriptors — Entering, Emerging, Developing, Expanding, Bridging, Reaching — rather than percentiles. A descriptor states what the student can do with language; a percentile states only where they rank.
A note on ELP assessments
Annual ELP assessments such as ACCESS for ELLs and ELPA21 are criterion-referenced against English language development standards. That is precisely why their results can be used for reclassification decisions (Section 5.5): a proficiency-level determination is a statement about attainment of a defined standard, not a ranking against other test-takers.
5. Choosing the Right Tool
| Purpose | Use |
|---|---|
| Decide what to teach tomorrow | Criterion-referenced (formative, rubric, mastery check) |
| Determine whether a student met a standard | Criterion-referenced |
| Make a reclassification/exit decision | Criterion-referenced ELP determination plus multiple measures |
| Screen a large population for follow-up | Norm-referenced, with caution |
| Establish eligibility requiring population comparison | Norm-referenced, with native-language and nonverbal data alongside |
| Report growth to a family | Criterion-referenced descriptors and work samples, not percentiles |
A 6th-grade multilingual learner's report shows a grade equivalent of 2.4 in reading. What does this score actually indicate?
The student reads at a 2nd-grade level and should be given 2nd-grade texts.
The student's raw score on the 6th-grade test equals the median raw score of 2nd graders on that same 6th-grade test.
The student has mastered 24 percent of the 6th-grade reading standards.
The student should be retained until reading performance reaches grade level.
A district uses a nationally normed English reading achievement test, normed on a predominantly native-English-speaking sample, as the sole basis for placing multilingual learners into remedial tracks. What is the primary technical objection?
The test lacks inter-rater reliability because multiple scorers are involved.
Norm-referenced tests cannot produce percentile ranks for students below grade level.
The comparison group is inappropriate for developing English learners, so scores confound English proficiency with reading achievement and may not drive a high-stakes decision alone.
Criterion-referenced tests are legally prohibited from being used for placement decisions.
Which assessment result is criterion-referenced and directly actionable for instructional planning?
The student scored at the 38th percentile in reading comprehension.
The student earned a stanine of 4 on the reading subtest.
The student's normal curve equivalent was 43.
The student mastered identifying main idea and sequencing events but has not yet mastered inferring word meaning from context.
Why do annual English language proficiency assessments such as ACCESS for ELLs report performance-level descriptors rather than percentile ranks?
Because they are criterion-referenced against English language development standards, so a level describes attainment of a defined standard rather than a ranking against other test-takers.
Because federal law prohibits reporting percentile ranks for any assessment administered to English learners.
Because percentile ranks cannot be calculated when a test includes listening and speaking components.
Because performance-level descriptors are norm-referenced scores expressed in words instead of numbers.
Sections you finish are checked off in the contents.