How accurate is the NIFTY test?
The NIFTY test is one of the most accurate blood tests to detect Down syndrome (as well as Edwards’ syndrome and Patau syndrome) available in the world.
The combined test, comprising a blood test and an ultrasound test (extensively used at the present), has a detection accuracy of 95%, while the accuracy of the NIFTY test is over 99%.
The company in Hong Kong that has developed and distributes this test, processed more than 200,000 blood samples until March 2014. There were absolutely no false negatives, that is, cases where the test gave negative results although the fetus had Down syndrome.
This is practically a detection accuracy of 100%. However, the clinical data collection has not yet been completed, and at the present we cannot speak of an accuracy of 100%, on the basis of the criteria on scientific studies, but only of over 99%. (In other words, at the present this is a screening test, not a diagnostic test.)
There was only one false positive (that is, cases where the fetus did not have Down syndrome, as shown by the test) in the largest clinical study conducted on over 10,000 samples. In comparison: the combined test gives approximately 200 false positives in 10,000 cases.
The accuracy of the NIFTY test can be negatively influenced by the following: maternal chromosome abnormalities (aneuploidy), chromosomal mosaicism, microdeletions, microduplications, multiple pregnancies (triplets or more).
|Statistics for NIFTY Test (as of 12/28/2013)|
|Total sample no. (cases)||241,517||1,744||540||179|
|Karyotype analysis (cases) *||5,560||1,031||295||86|
|Sensitivity (calculated using Karyotype no.)||-||99.65%(CI 98.98-99.92)||99.66%(CI 98.13-99.99)||100%(CI 95.38-100)|
|Specificity (calculated using Karyotype no.)||-||99.99%(CI 99.97-99.99)||99.98%(CI 99.96-99.99)||99.98%(CI 99.97-99.99)|
|*Number of cases undergone karyotype analysis in our partnered hospitals for further confirmation of the results/accuracy of NIFTY|