Performance des tests : hospital series (institution-based ) vs. population-based results – e.g., population-based studies have reported sensitivities in the range 24-38% whereas Eurofetus (institution-based) study reported a sensitivity of 61%.

Differences are due in part to : selection (prevalence in the study population and severity of the anomalies – more severe are more often detected) + operator-dependent issues – training, etc – in particular true for ultrasound screening. Other reasons: exclusions (malformations not detectable by u/s) – false positives assessed or not – routine u/s or not, etc