Research Article

Risk Balancing of Cold Ischemic Time against Night Shift Surgery Possibly Reduces Rates of Reoperation and Perioperative Graft Loss

Figure 2

(a) Increments of odds ratios (OR) for delayed graft function were calculated and plotted per increment of CIT-hours. A mechanistic asymptotic regression function ( = asymptotic, = scale, and = increment) with best estimated fit was chosen for further calculations. The function (black line) was finally identified with lowest SSE = 10.3141 and best = 0.94 (a). (b) The point of highest acceleration in risk increment was then calculated by insertion of the regression equation into the curvature formula with = 0.13 to 23.5 hours at an odds ratio of 1.9 (cross hairs at black (a) and blue lines (b)). The calculated CIT cut-off of 23.5 h was then used in univariable regression analysis to calculate the risk of delayed graft function development for CIT > 23.5 h to a hazard ratio of 3.713 (CI 2.215–6.225; ).
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