1. Generating New Knowledge in Cardiac Interventions
Eugene H. Blackstone, MD 
Anesthesiology Clinics 
Volume 31, Issue 2, Pages (June 2013)
DOI: /j.anclin
Copyright © 2013 Elsevier Inc. Terms and Conditions

2. Fig. 1
Fundamental logistic relation of a scale of risk (logit units) to absolute probability of an event. Logistic relation, shown when risk factors are translated into logit units,28 is depicted along horizontal axis and probability of the outcome event along vertical axis. Logistic equation is inserted, where exp is the natural exponential function.
Anesthesiology Clinics  , DOI: ( /j.anclin )
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3. Fig. 2
Covariable balance plot before and after propensity score matching on selected covariables. Symbols depict percent standardized differences for covariables between patients in less invasive and conventional groups. BMI, body mass index; BUN, blood urea nitrogen; COPD, chronic obstructive pulmonary disease; Dysfunct., dysfunction; HTN, hypertension; LV, left ventricular; Regurg., regurgitation; TV, tricuspid valve.
(Data from Johnston DR, Atik FA, Rajeswaran J, et al. Outcomes of less invasive J-incision approach to aortic valve surgery. J Thorac Cardiovasc Surg 2012;144:852–8.e3.)
Anesthesiology Clinics  , DOI: ( /j.anclin )
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4. Fig. 3
Distribution of propensity scores for conventional and less invasive approaches for aortic valve replacement.
(Data from Johnston DR, Atik FA, Rajeswaran J, et al. Outcomes of less invasive J-incision approach to aortic valve surgery. J Thorac Cardiovasc Surg 2012;144:852–8.e3.)
Anesthesiology Clinics  , DOI: ( /j.anclin )
Copyright © 2013 Elsevier Inc. Terms and Conditions

5. Fig. 4
Mirrored histogram of distribution of propensity scores for conventional (bars above zero line) and less invasive (bars below zero line) approaches for aortic valve replacement. Darkened area represents matched patient pairs, showing that they cover the complete spectrum of cases, but predominate in the central area (area of virtual equipoise).
(Data from Johnston DR, Atik FA, Rajeswaran J, et al. Outcomes of less invasive J-incision approach to aortic valve surgery. J Thorac Cardiovasc Surg 2012;144:852–8.e3.)
Anesthesiology Clinics  , DOI: ( /j.anclin )
Copyright © 2013 Elsevier Inc. Terms and Conditions

6. Fig. 5
Changing risk across propensity scores for mitral valve repair versus replacement. Because of small numbers of patients with mitral valve replacement in quintiles III through V, these quintiles are grouped together. Patient profiles are similar in each quintile, but differ across quintiles. Each symbol represents a death according to the Kaplan-Meier estimator. Vertical bars enclose asymmetric 68% confidence limits (CL); solid lines enclosed within dashed 68% CLs represent parametric survival estimates; numbers in parentheses are numbers of patients traced beyond that point. P-values are for log-rank test. (A) Quintile I. (B) Quintile II. (C) Quintiles III through V.
(From Gillinov AM, Wierup PN, Blackstone EH, et al. Is repair preferable to replacement for ischemic mitral regurgitation? J Thorac Cardiovasc Surg 2001;122:1131.)
Anesthesiology Clinics  , DOI: ( /j.anclin )
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7. Fig. 6
Linearized work flow for a clinical research study: Transforming information to data suited for analysis.
Anesthesiology Clinics  , DOI: ( /j.anclin )
Copyright © 2013 Elsevier Inc. Terms and Conditions