1. From the Department of Cardiology, Oslo University Hospital, Ullevaal, Norway (J.E.M., S.E.K., E.E.P., K.E., J.B., E.B., I.G., P.T.S.)
2. Institute of Informatics (K.L.), University of Oslo, Norway
3. Institute of Clinical Medicine (S.E.K., E.E.P., K.E., K.G., J.E.), University of Oslo, Norway
4. Institute of Clinical Medicine; University of Tromsø, Norway (E.B.).