Current status of data collection

Since 2014, data for TwinLife has been collected on a yearly basis. Therefore the sample is divided into two so called partial waves. The survey is conducted via household and telephone interviews as shown in the figure below. The second partial wave passes through the same questioning as the first partial wave each year.

  • Partial wave I: birth cohort 1990/91, 1997, 2003, 2009
  • Partial wave II: birth cohort 1992/93, 1998, 2004, 2010

Between September 2014 and May 2015 as well as between September 2015 and April 2016 data on the first household interviews for both partial waves were collected. In addition, the first partial wave was surveyed again by phone in winter 2015. Since October 2016, data on the first household interview of the first partial wave (all in all on 2,009 twin families from all over Germany) has been available to the scientific community. Starting in winter 2016, the families of the first partial wave have been interviewed a second time in their homes. In parallel, the second partial wave, consisting of 2,088 twin families, has been surveyed by phone for the first time.



Interviews were conducted in communities with more than 5,000 inhabitants throughout all German federal states. You can take a look at the distribution of the participating families in Germany right here.


Information about the availability of data for research puposes can be found right here!


The flyer for the data release can be found here!


All documentations can be found here!