Funding for this research was provided by:
The Danish National Research Foundation
The Lundbeck Foundation
Received: 15 August 2017
Accepted: 19 March 2018
First Online: 24 April 2018
Ethics approval and consent to participate
: According to Danish law, secondary analyses of pre-existing data in registers do not require consent from the individuals whose data are included in the register and approval by the official scientific ethical committees is not required, but approval is needed by governmental Data Protection Agency, which was obtained. The Danish Adoption Register was established by colleagues in the former ‘Psykologisk Institut’ in the 1960’es after permission from the Danish Ministry of Justice, and have been hosted in that institute and its successor, Institute of Preventive Medicine. The responsibility as Principal Investigator was transferred from the founders of the register to the former Director of the Institute of Preventive Medicine, Professor Thorkild IA Sørensen. The register is now deposited in the Danish National Archive and is not publicly available. Request to use the data for research purposes must be put forward to the Danish National Archive, which will seek permission to share the data with externally based researchers from Professor Thorkild IA Sørensen and after permission granted by the Danish Data Protection Agency.
: Not applicable.
: The authors declare that they have no competing interests.
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