Peter Byass, Umeå University (IMAGE) Umea University Caption This is Peter Byass, epidemiologist at Ume&aring; University and co-author of the article. Credit Mattias Pettersson Usage Restrictions This photo may only be used in the context related to this press release. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.