Table 3.
Input parameters for the economic analysis
| Parameter | Value | Source |
|---|---|---|
| Proportion of carrier parents eligible for paternal mutation NIPD | 29.7% | Table 1 – supplementary information |
| Uptake invasive testing | 43.0% | Questionnaire results |
| Uptake NIPD | 95.0% | Questionnaire results |
| Cost of invasive molecular testing for CF | £370 | Regional Genetics laboratory |
| Cost of counselling, invasive test and cytogenetics | £750 | Local fetal medicine unit |
| Cost of NIPD to exclude paternal CF mutation | £550 | Regional Genetics laboratory |
| Cost of NIPD to directly diagnose CF | £750 | Estimation from the Regional Genetics laboratory |
| Cost of phlebotomy | £4 | NHS reference costs15 |
| Cost of sending in NIPT sample | £5 | Local fetal medicine unit |
| Cost of feedback NIPT results | £27 | Unit Costs of Health and Social Care16 |
| Risk of procedure-related miscarriage with invasive testing | 0.5% | Tabor et al.4 |
Total costs of invasive testing were £370 + £750 = £1120. Total costs of NIPD were £550 + £4 + £5 + £27 = £586 for paternal exclusion and £750 + £4 + £5 + £27 = £786 for direct diagnosis. Costs of pretest genetic counselling and ultrasound for dating and exclusion of multiple pregnancies are not included as it applies equally to all scenarios.
NIPD, non-invasive prenatal diagnosis; CF, cystic fibrosis.