Split-dose bowel preparation improves adequacy of bowel preparation and gastroenterologists’ adherence to National Colorectal Cancer Screening and Surveillance Guidelines

Table 2 Patient and procedure characteristics by study year: 2009 is prior to split dosing, and 2011 is after split dosing

Characteristic	2009 (n = 1987)	2011 (n = 2238)	Total (n = 4225)	P value1
Age, yr
≤ 55	1096 (55.2)	1311 (58.6)	2407	< 0.001
55-65	606 (30.5)	674 (30.1)	1,280
65-75	233 (11.7)	253 (11.3)	486
≥ 75	52 (2.6)	0 (0)	52
Female	1099 (55.3)	1182 (52.8)	2281	0.100
Race/ethnicity
White or Hispanic	1652 (83.1)	1846 (82.5)	3498	< 0.001
Black	131 (6.6)	160 (7.1)	291
Asian	128 (6.4)	129 (5.8)	257
Other	20 (1.0)	100 (4.5)	120
BMI (kg/m2), mean (SD)	1871 (94.2)	2213 (98.9)	4084	0.610
Current narcotics2 use
Yes	131 (6.6)	163 (7.3)	294	0.360
No	1856 (93.4)	2066 (92.3)	3922
Current TCA use
Yes	47 (2.4)	31 (1.4)	78	0.020
No	1940 (97.6)	2198 (98.2)	4138
Type II diabetes
Yes	164 (8.3)	201 (9.0)	365	0.400
No	1823 (91.7)	2037 (91.0)	3860
Bowel preparation quality
Adequate or excellent	592 (30.6)	886 (39.6)	1478	< 0.001
Good	1044 (54.0)	1048 (46.9)	2092
Fair	209 (10.8)	189 (8.5)	398
Inadequate or poor	89 (4.6)	113 (5.1)	202
Polyp presence
Yes	745 (37.5)	807 (36.1)	1552	0.330
No	1242 (62.5)	1431 (63.9)	2673
Preparation type
8L PEG	5 (0.3)	17 (0.8)	22	< 0.001
MiraLAX/Gatorade	541 (28.3)	1228 (57.1)	1769
4L PEG, GoLYTELY, NuLYTELY, Colyte, TriLyte	1015 (53.1)	771 (35.9)	1786
Half-Lytely,Osmoprep, Moviprep, and others	352 (18.4)	133 (6.2)	485
Preparation type
MiraLAX/Gatorade	541 (28.3)	1228 (57.1)	1769	< 0.001
4L PEG, GoLYTELY, NuLYTELY, Colyte, TriLyte	1015 (53.1)	771 (35.9)	1786
Half-Lytely, Osmoprep, Moviprep, and others	357 (18.7)	150 (7.0)	507
GI fellow presence
Yes	187 (9.4)	303 (13.5)	490	< 0.001
No	1800 (90.6)	1935 (86.5)	3735

All values are n (%), unless otherwise specified. The total number of patients for each characteristic may not add to total (n = 4225) due to missing data.

¹From testing differences in the distribution of characteristics between years, based on t-test for continuous variables and χ² test for categorical variables;

²Narcotics are opioids and their derivatives. Common narcotics include morphine, heroin, hydrocodone, oxycodone, methadone, and clonitazene. BMI: Body mass index; TCA: Tricyclic antidepressant.