Perinatal mortality rates do not contain what they purport to contain.

Three cases of perinatal death, of which two needed to be included in and one excluded from national perinatal mortality statistics, were presented to 1004 specialist and trainee obstetricians in northern Belgium (ie, Flanders) and the Netherlands. Of the respondents (52%), 69% admitted that they would report none of the cases and 13% would report all of them. Overreporting occurred twice as often and underreporting ten times as often as correct reporting--only 6% would apply the current regulations for registration of perinatal mortality correctly in all three cases. Although the statutory regulations with regard to the cases were similar in the two countries, there were differences between Belgian and Dutch doctors in their reporting of these three cases. This indicates that Belgian and Dutch perinatal mortality statistics do not measure the same thing and that neither contains what it purports to contain. The findings cast doubts on the validity of using national perinatal mortality figures as indicators of perinatal health or perinatal care in and between European countries.