Study selection, data collection and bias
Retrieved studies were filtered on title and abstract and where there was any doubt, the study was accepted to the next level. Only original studies equal to or above OCEBM Level 4 evidence(8)that reported on the presence of a diagonal ear lobe crease in patients undergoing coronary angiography were included. Selected studies were then assessed independently by both authors for quality and bias using CASP checklists(9). Differences were resolved by discussion. Objective data were extracted from the studies and summarized into tables and meta-analysis was performed using Revman 5.4(10).