Babu Kunadian research fellow, Joel Dunning specialist registrar in cardiothoracic surgery, Anthony P Roberts clinical effectiveness specialist adviser, Robert Morley clinical audit lead, Darragh Twomey clinical teaching fellow, James A Hall consultant cardiologist et al
Kunadian B, Dunning J, Roberts A P, Morley R, Twomey D, Hall J A et al.
Cumulative funnel plots for the early detection of interoperator variation: retrospective database analysis of observed versus predicted results of percutaneous coronary intervention
BMJ 2008; 336 :931
doi:10.1136/bmj.39512.529120.BE