How to Compare Different NIPT Brands?
NIPT tests are not the same. Tests may differ in terms of scope, technology, clinical performance, laboratory quality, test failure rate, and counseling support. Therefore, the most accurate test choice should be made through physician evaluation, taking into account the characteristics of the pregnancy and the needs of the family.
1. Scope
Some NIPT tests only evaluate the most common chromosome abnormalities:
- Trisomy 21 — Down syndrome
- Trisomy 18 — Edwards syndrome
- Trisomy 13 — Patau syndrome
In wider scope tests, in addition to these:
- Sex chromosome abnormalities
- Rare chromosome abnormalities
- Microdeletions
- Deletions / Duplications
- Single-gene hereditary and de novo genetic diseases
- Fetal sex or fetal RhD status
may also be included.
2. Technology Used
The analysis method and bioinformatic algorithms used in NIPT tests may change from laboratory to laboratory. This difference can affect which diseases the test can screen, its performance at low fetal DNA fractions, and the reliability of the result report.
3. Clinical Performance
Scientific performance data of NIPT tests, such as sensitivity, specificity, false positive rate, positive predictive value (PPV), and negative predictive value (NPV), are not the same.
Therefore, it is not enough for a test to be named simply 'NIPT'; by which clinical studies the test has been validated, on how many samples it has been evaluated, and for which conditions it offers reliable performance should be considered.
4. Test Failure Rate
In some NIPT tests, results cannot be provided due to low fetal DNA fractions or technical reasons. This condition is called 'test failure' or 'no result'. When choosing a test, tests with low failure rates that offer reliable reporting should be preferred.
5. Laboratory Quality and Accreditation
The experience, quality standards, and accreditations of the laboratory where the test is processed are important. Especially for genetic tests, laboratories operating in compliance with international quality standards should be preferred.