Annales de Biologie Clinique
MENUCost-effectiveness threshold of first-trimester Down syndrome maternal serum screening for the use of cell-free DNA as a second-tier screening test Volume 79, issue 4, Juillet-Août 2021
- Key words: Non-invasive prenatal testing, Down syndrome, prenatal screening, economic analysis, cost-effectiveness ratio
- DOI : 10.1684/abc.2021.1656
- Page(s) : 331-8
- Published in: 2021
Introduction: We aimed to identify the most relevant cost-effectiveness threshold of first-trimester Down syndrome (DS) maternal serum screening (T21T1) for the use of cell-free DNA (cfDNA) as a second-tier test in the French context. Method: A cost-effectiveness analysis was performed on 108,121 singleton pregnancies using a simulation model. The threshold of T21T1 screening was ranged from 1/51 to 1/1,000 in steps of 1/50. The most relevant threshold was based on cost-effectiveness ratio (CER; costs = direct medical costs after T21T1 screening/ effectiveness = number of DS cases identified). Results: In the sample, 161 cases of DS were identified. At the threshold of ≥ 1/50, 47.2% of total DS cases were diagnosed. In the simulation model, for a threshold ≥ 1/250, 73.9% of total DS cases were diagnosed, for ≥ 1/500, 78.8% and for ≥ 1/1,000, only two additional cases were diagnosed. The slope of the cost increase was slight from threshold ≥ 1/250 (978,634 €), then steep up to 1/500 (1,966,576 €) and increased exponentially to 1/1,000 (3,980,216 €). The CER was 38,560 for a threshold ≥ 1/500. Conclusion: The most cost-effective threshold for cfDNA as a second-tier test seems to be ≥ 1/500. For higher thresholds, costs increase dramatically for only a few additional cases of DS identified.