It has 68 maternity units where 99.8% of all births (of Z 500 g) occur. For each newborn of at least 500 g, an official perinatal form is completed, mostly by the midwife, which contains information on birth weight and gestational age. The form is sent to the SPE, where an error de- tection program controls all data and feedback is provided (Cam- mu et al., 2002). The qualitative assessment of data obtained by the SPE showed that there is less than 5% difference between electronic data and data derived from medical files (Cammu et al.,
2002).