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).