Table 2.
Data of the 2011–2018 CF NBS algorithm: IRT1/IRT2 + LACT protocol and IRT1/DNA protocol separately
| CF NBS 2011–2018 | |||
|---|---|---|---|
| IRT1/IRT2 + LACT | IRT1/DNA | IRT1/IRT2 + LACT + IRT1/DNA (actual strategy) | |
| Newborns screened for CF | 231,845 | 231,845 | 231,845 |
| Newborns with negative screening | 231,370 | 231,604 | 231,227 |
| Non CF newborns with negative screening (TNs) | 231,362 | 231,599 | 231,225 |
| Number of retesting (IRT2) | 906 | – | 906 |
| Number of sweat tests (newborns with positive screening) | 475 | 241 | 618 |
| Number of sweat tests after positive IRT1 + LACT | 157 | – | – |
| Number of sweat tests after positive retesting (IRT2) | 318 | – | – |
| Non CF newborns with positive screening (FPs) | 430 | 194 | 568 |
| CF newborns with positive screening (TPs) | 44 | 47 | 50 |
| CF newborns with negative screening (FNs) | 8 | 5 | 2 |
| CF newborns diagnosed for meconium ileus | 7 | 7 | 7 |
| Sensitivity (%) | 84.61a | 90.38a | 96.15 |
| Specificity (%) | 99.81a | 99.91a | 99.75 |
| Positive predictive value (%) | 9.26a | 19.50a | 8.09 |
| Negative predictive value (%) | 99.99a | 99.99a | 99.99 |
aThese values are different from those of Table 2 of Terlizzi et al (2019) [22] because our analysis covered 1 year longer (2011–2018 vs. 2011–2017)