Table 17:
Additional Model Inputs Used in the Scenario Analyses
| Mean; Distribution (Alpha; Beta) | |||
|---|---|---|---|
| Screening Option | Detection Rate | False-Positive Rate | Sources |
| Inclusion of Sex Chromosome Aneuploidies and/or Microdeletions | |||
| Sex chromosome aneuploidies | 93.8%; beta (90; 6) | 0.4%; beta (4; 964) | Badeau et al, 201767 |
| 22q11.2 deletion | 90% or 75% or 50%; fixed | 0.1%; fixed | Ravi et al, 2018100; Martin et al, 2018102 |
| NIPT Performance Based on Cochrane Reviewa | |||
| Trisomy 21 | 99.2%; beta (87.3; 0.7) in first-tier NIPT | 0.1%; beta (20; 19,980)b in first-tier NIPT | Badeau et al, 201767 |
| 99.2%; beta (244; 2) in second-tier NIPT | 0.1%; beta (4; 3,996)a in second-tier NIPT | Badeau et al, 201767 | |
| Trisomy 18 | 90.9%; beta (20; 2) in first-tier NIPT | NA | Badeau et al, 201767 |
| 98.2%; beta (110; 2) in second-tier NIPT | NA | Badeau et al, 201767 | |
| Trisomy 13 | 62.5%; beta (5; 3) in first-tier NIPT | NA | Badeau et al, 201767 |
| 100%; fixed in second-tier NIPT | NA | Badeau et al, 201767 | |
| Lower Trisomy 21 Risk Cutoff for Second-Tier NIPT | |||
| eFTSb (risk cutoff: 1/1,000) | 94.8%; beta (129.9; 7.1) | 10.5%b; beta (71.8; 612.2) | Huang et al, 20152 |
| MSS (risk cutoff: 1/700) | 80.8%; beta (48.5; 11.5) | 10.1%; beta (3024; 26,976) | BORN data |
| Lower Trisomy 21 Risk Cutoff and Higher Acceptance of Further Testing for Second-Tier NIPT | |||
| Higher acceptance rate after positive results from traditional prenatal screening | 90% | — | Estimate |
Abbreviations: eFTS, enhanced first-trimester screening; MSS, maternal serum screening (also known as quadruple screening); NA, not applicable; NIPT, noninvasive prenatal testing.
a
Test failures (for any reason) were excluded in estimating the performance of NIPT.67
b
Combined false-positive rate for trisomies 21, 18, and 13.