. Author manuscript; available in PMC: 2010 Aug 16.

Published in final edited form as: Am J Obstet Gynecol. 2007 Jul;197(1):78.e1–78.e7. doi: 10.1016/j.ajog.2007.02.046

Table II.

Subject Characteristics Evaluated as Possible Risk Factors for Ileus or Small Bowel Obstruction

Variables Tested	Ileus or SBO		^# P-value
Variables Tested	Yes N=19	No N=303	p-value
Age, years (mean ± SD)	70.6 ± 5.5	60.8 ± 10.2	<0.0001
BMI, kg/m² (mean ± SD)	26.6 ± 4.5	27.1 ± 4.5	0.68
Prescription Medications (Median, Interquartile Range)	4 (2 – 5)	3 (2 – 5)	0.78
Prior Abdominal Surgery	19 (100%)	247 (82%)	0.054
Comorbidity Index^*	5.0 ± 3.3	3.9 ± 3.0	0.09
Current Smoker	2 (10.5%)	21 (7.0%)	0.64

SD = Standard Deviation

BMI = Body Mass Index

Student t-test were used for continuous variables (e.g., age, BMI, comorbidity index), Mann-Whitney test was used for skewed data (e.g., for number of medications), and Chi-square analysis was used for categorical variables (e.g., prior abdominal surgery, current smoker).

Comorbidity Index: the total score is the sum of severity ratings 1 to 4 (mild to very severe) in each of 14 organ-specific categories.