Table 1 Results of the various screening strategies of CF NBS adopted over time (1984–2018) by the CF Referral Tuscan Center of Florence. () percentage related to all CF cases of the period in column
From: Cystic fibrosis in Tuscany: evolution of newborn screening strategies over time to the present
SQRID (1984–1991) | IRT1/IRT2 (1991–1994) | IRT1/IRT2 + LACT (1992–2010) | IRT1/IRT2 + LACT + IRT1/DNA (2011–2018) | Total | |
|---|---|---|---|---|---|
Newborns screened for CF | 113,288 | 59,546 | 514,841 | 231,845 | 919,520 |
Total CF cases | 37 | 19 | 143 | 59 | 258 |
Newborns with negative screening | 113,070 | 59,400 | 513,619 | 231,227 | 917,316 |
Non CF newborns with negative screening (TNs) | 113,060 | 59,397 | 513,603 | 231,225 | 917,285 |
Number of retesting (IRT2) | – | 936 | 2977 | 906 | 4819 |
Newborns with positive screening (number of sweat test) | 218 | 146 | 1222 | 618 | 2204 |
Non CF newborns with positive screening (FPs) | 196 | 131 | 1110 | 568 | 2005 |
CF newborns with positive screening (TPs) | 22 (59.4%) | 15 (79.0%) | 112 (78.3%) | 50 (84.7%) | 199 (77.1%) |
CF newborns with negative screening (FNs) | 10 (27.0%) | 3 (15.8%) | 16 (11.2%) | 2 (3.4%) | 31 (12.0%) |
CF newborns diagnosed for meconium ileus | 5 (13.5%) | 1 (5.2%) | 15 (10.5%) | 7 (11.9%) | 28 (10.9%) |
Sensitivity (%) | 68.75 | 83.33 | 87.50 | 96.15 | – |
Specificity (%) | 99.82 | 99.77 | 99.78 | 99.75 | – |
Positive predictive value (%) | 10.09 | 10.27 | 9.16 | 8.09 | – |
Negative predictive value (%) | 99.99 | 99.99 | 99.99 | 99.99 | – |