The eight surveys of the LifeObs project will be coupled with methodological innovations regarding the preparation of longitudinal surveys, multi-mode data collection, the use of new software, and the enrichment of surveys via matching with various administrative data sources.
The frequency of twin births has significantly increased in developed countries, doubling since the 1970s (see Figure 1). Two main factors have contributed to this development, namely the rise in the use of medically assisted reproduction techniques, as well as a substantial increase in the mean age at childbearing (Pison et al., 2015). This ’boom’ in the birth of twins constitutes a public health ...
