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Exhibits 53 to 55

Exhibit 53. Results of logistic regression using the 60% derivation set, including each of the five surgical procedures as a possible risk factor

VariableEstimatetValueProbability
Intercept-5.47-4.820.0000
Emergency surgery0.743.050.0023
Chronic kidney disease-1.84-2.490.0130
Male0.01302.370.0180
History of MRSA1.504.740.0000
No. of surgeons*0.792.390.0168
Postop admission2.589.730.0000
Preop glucose*0.000.550.5893
Preop hemoglobin-0.24-4.040.0001
Preop stay0.020.820.4096
Surgery duration0.001.610.1073
Herniorrhaphy0.882.900.0037

* Additional Intermountain risk factor.

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Exhibit 54. Results of logistic regression using the 40% validation set, and including each of the five surgical procedures as a possible risk factor

VariableEstimatetValueProbability
Intercept-4.97-3.660.0003
Emergency surgery0.010.040.9686
Chronic kidney disease-1.54-2.050.0400
Male0.130.600.5510
History of MRSA1.123.100.0020
No. of surgeons*0.831.820.0695
Postop admission1.958.070.0000
Preop glucose*0.00-1.000.3223
Preop hemoglobin-0.17-2.620.0090
Preop stay0.041.130.2574
Surgery duration0.003.070.0021
Herniorrhaphy0.842.760.0059

* Additional Intermountain risk factor.

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Exhibit 55. Results of logistic regression using the combined derivation and validation sets and including each of the five surgical procedures as a possible risk factor

VariableEstimatetValueProbability
Intercept-5.41-6.370.0000
Elective surgery0.420.420.0246
Chronic kidney disease-1.68-3.200.0014
Male0.311.990.0469
History of MRSA1.355.700.0000
No. of surgeons*0.803.050.0023
Postop admission0.002312.740.0000
Preop glucose*0.00-0.270.7842
Preop hemoglobin-0.19-4.230.0000
Preop stay0.041.510.1308
Surgery duration0.003.420.0006
Herniorrhaphy0.864.020.0001

* Additional Intermountain risk factor.

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Current as of December 2012
Internet Citation: Exhibits 53 to 55. December 2012. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/research/findings/final-reports/ssi/ssiexh53-55.html