Improving the Measurement of Surgical Site Infection Risk Stratification/Outcome Detection

Exhibits 44 to 46

Exhibit 44. Results of logistic regression using the derivation dataset for only appendectomy

Variable Estimate tValue Probability
Intercept -3.45066 -1.04967 0.31289
History of cancer 0.896303 0.974859 0.32970
Emergency surgery 0.32970 -0.96643 0.33384
Male 0.488666 0.768574 0.768574
Postop admission 2.453247 3.652926 0.00026
Postop hematocrit -0.17629 -2.12084 0.04042
Postop hemoglobin 0.272209 0.822076 0.42317
Preop hemoglobin -0.0374 -0.0374 0.79751

Postop = postoperative; Preop = preoperative.

Return to Document

Exhibit 45. Results of logistic regression using the validation dataset for only appendectomy

Variable Estimate tValue Probability
Intercept -4.59592 -2.06151 0.04255
History of cancer 0.855832 0.736814 0.46124
Emergency surgery 0.655977 1.172465 0.24101
Male 0.586734 1.019488 0.30824
Postop admission 2.572595 4.931689 0.00000
Postop hematocrit -0.15581 -1.68912 0.09748
Postop hemoglobin 0.310595 1.163695 0.24698
Preop hemoglobin -0.04081 -0.31694 0.75426

Postop = postoperative; Preop = preoperative.

Return to Document

Exhibit 46. Results of logistic regression using the combined dataset for only appendectomy

Variable Estimate tValue Probability
Intercept -3.90766 -2.4378 0.01642
History of cancer 0.749083 1.068061 0.28549
Emergency surgery 0.130644 0.331969 0.73991
Male 0.619657 1.471467 0.14148
Postop admission 2.515271 6.19406 0.00000
Postop hematocrit -0.15793 -2.74004 0.00744
Postop hemoglobin 0.304609 1.439065 0.16263
Preop hemoglobin -0.07631 -0.6829 0.51247

Postop = postoperative; Preop = preoperative.

Return to Document

Page last reviewed December 2012
Page originally created December 2012
Internet Citation: Exhibits 44 to 46. Content last reviewed December 2012. Agency for Healthcare Research and Quality, Rockville, MD. http://www.ahrq.gov/research/findings/final-reports/ssi/ssiexh44-46.html