Information for twins

If you are a twin and participates in one of our studies, we would like to take this opportunity to thank you for your participation.

Welcome to the Swedish Twin Registry

We would not be able to do any research without your help, and we agree with Svenska Dagbladet, which has described you twins as "heroes of science"!

Can you sign up for the Twin Registry?

We would like to welcome those of you who are not yet participating in our research, but would want to do that. However, there have been many questions about HOW and IF you can sign up for the Twin Registry. This, we will of course clarify.

The Swedish Twin Registry has in accordance with the Ethical Review Act, received permission to get information about all twin births that take place and are registered in Sweden from the Swedish Birth Registry. Using that information, we can contact these twins or their guardian with an invitation to participate in the Swedish Twin Registry when there is a current research project. This therefore means that you are not automatically included in the Swedish Twin Registry, you must first be invited and then accept to be included.

This also means that one cannot register yourself to the Twin Registry. Most studies are based on age, which means that all twins born in a particular year will be invited simultaneously. Currently, the first contact with the twins is when they have reached their ninth birthday.

Ethics and morals are very important to us

Medical research provides knowledge that can help to improve individual and group health. Meanwhile, no one participating in a research study may be subjected to unnecessary discomfort or harm. Therefore all research projects are examined prior to the start by an independent ethics board. The Ethical Review Board assesses wheather the relationship between potential risk and potential benefit to the individual is acceptable and whether the information given to the participants in the study is accurate and understandable. More information is available on the Research Council's information pages "rules and guidelines for research,"

All of us who work at the Swedish Twin Registry take this very seriously and are happy to answer any questions. You can reach us at or on Facebook.
Responsible for the Swedish Twin Registry is Patrik Magnusson, researcher.

Follow us on Facebook

The Twin Registry has a  Facebook group for twins and participants. We have noticed that there is a lot of information that interests you, but also that you have many questions. Please follow us on our Facebook page where we hope for an open dialogue about research and, above all, to show what your participation contributes to for future research.

Ongoing studies

Currently underway are about 30 projects based on the Twin Registry. These studies cover a wide range of public health issues, among others dementia diseases, allergies, cancer and cardiovascular diseases. Other research projects address issues of gender differences in health and life situation.

If you would like more information on any of our studies, please click the tab named "our projects". There you can select the study or studies you are interested in.

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