Jon-David Schwalm, McMaster University (IMAGE) McMaster University Caption Jon-David Schwalm, an associate professor of medicine at McMaster, a scientist at the PHRI and an interventional cardiologist at Hamilton Health Sciences. Credit Population Health Research Institute (PHRI) of McMaster University and Hamilton Health Sciences Usage Restrictions To be used with stories about this study. 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.