Dissertation 11 May 2017: Johan Zetterqvist

On Thursday May 11, Johan Zetterqvist will defend his thesis "Statistical methods for twin and sibling designs". Assistant Professor Theis Lange from the University of Copenhagen will be his opponent. Johan's supervisors are Arvid Sjölander, Yudi Pawitan, Henrik Larsson, and Paul Lichtenstein

Johan focuses on twin and sibling studies, which are valuable in that they allow adjustment for potential confounding factors that are impossible or hard to measure. By measuring associations ‘within-cluster’ it is possible to adjust for many factors that are shared between individuals in the same cluster. Using Swedish national registers, it is possible to obtain information about a large number of potential confounders. While this gives medical researchers great opportunities to control for confounding, it also increases the risk of model misspecification leading to biased estimates. One strategy to reduce the risk of such bias is to use doubly robust(DR) estimation. In DR estimation two working models are combined in such a way that the resulting estimate will remain asymptotically unbiased when one of the models is misspecified.

Time and location: 09:00, May 11 2017 in the lecture hall Atrium, Nobels väg 12B, Karolinska Institutet, Solna