Variability in data: The Society of Thoracic Surgeons National Adult Cardiac Surgery Database
Received 15 July 2009; received in revised form 3 February 2010; accepted 26 February 2010. published online 24 May 2010.
Objective
Since 1989, data have been reported to the Society of Thoracic Surgeons National Adult Cardiac Surgery Database for quality improvement. This information is also data mined for national quality indicators, policy initiatives, and research. Such use has important limitations, because data elements cannot be verified for accuracy. We determined variability of disease etiology and operative data database elements when abstracted by untrained physician abstractors.
Methods
We selected 30 patients who underwent cardiovascular surgery from January to December 2005 (10 each of coronary artery bypass grafting, mitral valve repairs, and aortic valve and associated aortic procedures). Four abstractors (2 cardiothoracic residents and 2 fellows) abstracted 28 variables. Results were compared with abstraction performed by a professional abstractor.
Results
Median percentage agreement among all cases was 89% (range, 42%–100%). Agreements were 94% (28%–100%) for mitral valve, 84% (48%–100%) for aortic valve, and 93% (35%–100%) for coronary artery bypass grafting. Among the aortic valve group, etiology of aortic valve disease had poor agreement (68%) because of cases in which multiple definitions could apply. Degree of valvular regurgitation also had poor agreement (median, 67%; range, 28%–95%). Number of internal thoracic artery grafts and absence of significant valvular disease were reported consistently. Agreements between types of aortic valve procedure and between methods of mitral valve repair (65% and 83%, respectively) were less than expected.
Conclusions
We found variable agreement among untrained data abstractors. This has important implications regarding interpretation of database studies with de-identified data. Without good quality control and consistent standardized definitions, aggregate data in clinical databases may be suspect.
aDepartment of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
bDivision of Cardiovascular Surgery, Mayo Clinic, Rochester, Minn
Address for reprints: Hartzell V. Schaff, MD, Mayo Clinic, 200 1st St SW, Rochester MN 55905.
Supported by grant No. 1 TL1 RR024152-01 from the National Center for Research Resources (NCRR) of the National Institutes of Health (NIH) and the NIH Roadmap for Medical Research. Its contents are solely the responsibility of the authors and do not necessarily represent the official view of NCRR or NIH. Information on NCRR is available at http://www.ncrr.nih.gov/. Information on Reengineering the Clinical Research Enterprise can be obtained from http://nihroadmap.nih.gov/clinicalresearch/overviewtranslational.asp.
ABSTRACT