THE APPLICATION AND FACTORS INFLUENCING THE IMPLEMENTATION OF NON-INVASIVE PRENATAL TESTING (NIPT) WORLDWIDE: A SYSTEMATIC REVIEW
The purpose of this paper is to systematically review the current scientific evidence of the application of non-invasive prenatal testing (NIPT) besides Trisomy 21, 13 and 18 and factors influencing the implementation of NIPT worldwide. Three databases were searched for related articles using chosen keywords. The PRISMA guidelines were used for the purpose of standardizing systematic review writing. The assessment of the quality of the articles was done using Crowe Critical Appraisal Tool (CCAT) version 4.1. Nine articles were accepted as meeting the inclusion criterion and were reviewed. Six applications of NIPT besides Trisomy 21, 13 and 18 were identified: 1) a rare de novo 18p terminal deletion with inverted duplication, 2) skeletal dysplasia, 3) foetal achondroplasia, 4) microdeletion abnormalities of foetal chromosome 15, 5) detection of various foetal sex chromosome abnormalities (SCAs) (Turner syndrome, Triple X syndrome, Klinefelter syndrome and XYY syndrome) and 6) Duchenne and Becker muscular dystrophies. This review identified six factors that influenced the implementation of NIPT: 1) the test detection rate or accuracy, 2) early access to conduct test, 3) cost-effectiveness of implementing NIPT (for the detection of Down Syndrome), 4) availability of informed consent process (preference of service users), 5) education level of service users and 6) a measure of reassurance to service users. To conclude, this review had collated data on the utilization of NIPT in the screening of various chromosomal and genetic disorders and was able to delineate factors influencing the clinical implementation of NIPT from the perspective of health professionals and pregnant women. The findings are expected to contribute towards future implementation of NIPT in Malaysia.