A prospective cohort study of the relationship between the withdrawal time and the detection rate of colorectal adenoma

Figures & data

Figure 1. Flow chart of research.

Table 1. Baseline characteristics of the patients and bowel preparation.

	WT ≤ 6 min	p Value	WT > 6min	p Value	Total
N	220		217		437
Age, year	52.8 ± 13.0	.527	53.6 ± 13.1	<.001***	53.2 ± 13.0
<50	37.5 ± 6.9		38.1 ± 6.7		37.8 ± 6.8
≥50	61.2 ± 5.9		61.6 ± 6.9		61.4 ± 6.4
Sex		.157		.016*
Male	89 (40.5)		88 (40.6)		177 (40.5)
Female	131 (59.5)		129 (59.4)		260 (59.5)
Body mass index, kg/m^2	23.3 ± 4.0	.937	23.6 ± 3.6	.025*	23.5 ± 3.8
<25.0	158 (71.8)		145 (66.8)		303 (69.3)
25.0–29.9	54 (24.5)		64 (29.5)		118 (27.0)
≥30.0	8 (3.6)		8 (3.7)		16 (3.7)
Defoaming rate score	7.9 ± 1.7	.685	8.0 ± 1.7	.760	7.9 ± 1.7
≥6	21 (9.5)		18 (8.3)		39 (8.9)
<6	199 (90.5)		199 (91.7)		398 (91.1)
BBPS	7.2 ± 1.3	.524	7.3 ± 1.4	.516	7.3 ± 1.4
≥6	14 (6.4)		18 (8.3)		32 (7.3)
<6	206 (93.6)		199 (91.7)		405 (92.7)
Primary colonoscopy		.035*		.324
Yes	127 (57.7)		110 (50.7)		237 (54.2)
No	93 (42.3)		107 (49.3)		200 (45.8)
Hypertension		.262		.228
Yes	46 (20.9)		40 (18.4)		86 (19.7)
No	174 (79.1)		177 (81.6)		351 (80.3)
Diabetes		.918		.842
Yes	11 (5.0)		19 (8.8)		30 (6.9)
No	209 (95.0)		198 (91.2)		407 (93.1)
Diet preparation		<.001***		.623
Yes	207 (94.1)		206 (94.9)		413 (94.5)
No	13 (5.9)		11 (5.1)		24 (5.5)
Previous abdominal surgery		.665		.944
Yes	69 (31.4)		81 (37.3)		150 (34.3)
No	151 (68.6)		136 (62.7)		287 (65.7)

The independent samples t test was done for each index in the two groups with WT ≤ 6 min and WT > 6 min. p Value <0.1 use *;<0.01 use **;<0.001 use ***; normally distributed data for measurement data are expressed as mean ± SD, and count data are expressed as %; BBPS: Boston bowel preparation scale; WT: withdrawal time.

Table 2. Odds ratios for ADR in Univariate and Multivariate logistic regression in WT ≤6 min.

Characteristics	Univariate
	Coef	OR	95%CI	p Value
Sex
Female	Reference
Male	0.634	1.89	0.78–4.58	.161
Primary Colonoscopy
No	Reference
Yes	1.001	2.72	0.97–7.66	.058
Hypertension
No	Reference
Yes	0.643	1.90	0.73–4.98	.191
Diabetes
No	Reference
Yes	−0.111	0.90	0.11–7.34	.918
Previous Abdominal Surgery
No	Reference
Yes	−0.219	0.80	0.30–2.15	.663
Diet Preparation
No	Reference
Yes	15.476	5,262,414.87	–	.993
Age
<50	Reference
≥50	0.181	1.20	0.47–3.08	.707
Defoaming rate score
<6	Reference
≥6	−0.457	0.63	0.17–2.35	.495
BMI
BMI < 25.0	Reference
25.0 ≤ BMI < 30.0	0.104	1.11	0.41–3.00	.838
BMI ≥ 30.0	−59.915	0.00	–	1.000
BBPS
<6	Reference
≥6	−0.987	0.37	0.10–1.45	.155

BBPS: Boston bowel preparation scale; BMI: body mass index.

Table 3. Odds ratios for ADR in univariate and multivariate logistic regression in WT >6 min.

Characteristics	Univariate				Multivariate
	Coef	OR	95%CI	p Value	Coef	OR	95%CI	p Value
Sex
Female	Reference				Reference
Male	0.766	2.15	1.15–4.03	.017*	0.832	2.30	1.19–4.43	.013*
Primary Colonoscopy					Not include
No	Reference
Yes	0.314	1.37	0.73–2.55	.323
Hypertension					Not include
No	Reference
Yes	0.500	1.65	0.78–3.49	.191
Diabetes					Not include
No	Reference
Yes	0.110	1.12	0.38–3.26	.841
Previous Abdominal Surgery					Not include
No	Reference
Yes	0.023	1.02	0.54–1.94	.944
Diet Preparation					Not include
No	Reference
Yes	0.392	1.48	0.31–7.08	.623
Age
<50	Reference				Reference
≥50	1.714	5.55	2.25–13.71	<.001***	1.757	5.80	2.32–14.47	<.001***
Defoaming Rate Score					Not include
<6	Reference
≥6	−0.191	0.83	0.28–2.44	.730
BMI					Not include
BMI < 25.0	Reference
25.0 ≤ BMI < 30.0	0.627	1.87	0.97–3.62	.062
BMI ≥ 30.0	0.245	1.28	0.25–6.65	.771
BBPS					Not include
<6	Reference
≥6	−0.481	0.62	0.22–1.74	.362

p Value <.1 use *, <.01 use **, <.001 use ***; reference was the subject of comparison; Significant p-values from single-factor regression were included in the multi-factor regression model.

BBPS: Boston bowel preparation scale; BMI: body mass index.

Figure 2. OR of ADR and WT in total study population. When OR= 0.997, WT= 5.997. When OR= 3.092, WT= 8.240. OR: odds ratio; ADR: adenoma detection rate; WT: withdrawal time.

Figure 3. Longer than 6 min, WT for ADR. The sub dataset of WT >6 min: when OR= 1.00, WT= 8.01. WT: withdrawal time; ADR: adenoma detection rate; OR: odds ratio.

Data availability statement

The experimental data are non-public; if the industry needs data support, please contact the corresponding authors of this paper directly.