Table 4.

Characteristics of the birth defect registries used for comparison with Lombardy birth defects registry

Characteristic	Finland	Georgia	Hawaii	Lombardy
Type of registry	Population-based	Population-based	Population-based	Population-based
Size (births/year)	58,000	50,019	20,636	12,008
Time for diagnosis	Up to 1 y	Up to 6 y	Up to 1 y	Up to 1 y
Compulsory	Yes	Yes	Yes	No
Defects in abortion/terminations considered?	Yes	Yes	Yes	Not yet
Case ascertainment	Passive	Active	Active	Passive
Sources:
Hospital reports	Yes	Yes	Yes	Yes
Pathology reports	Yes	Yes	Yes	Yes
Cytogenetic lab reports	Yes	Yes	Yes	Yes
Other registries	National registers of abortions and births	No	No	No
Hospital discharges	Yes	Yes	Yes	Yes
Death certificates	Yes	Yes	Yes	Yes
Birth certificates	Yes	Yes	Yes	Yes
Fetal death certificates	No	Yes	Yes	No