Harriette Van Spall, McMaster University (IMAGE) McMaster University Caption Harriette Van Spall, first author and principal investigator of the study, a researcher at the Population Health Research Institute of McMaster University and Hamilton Health Sciences. Credit McMaster University Usage Restrictions None 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.