Patient willingness for repeat screening and preference for CT colonography and optical colonoscopy in ACRIN 6664: the National CT Colonography trial

Figures & data

Table 1 Comparison of participants with information available on patient preference compared with those for the entire trial

Variable	Analysis set (N=2,310)	Failed to return questionnaire (N=290)	Accrued into main study (N=2,600)
Age, mean (range)	58.39 (50–86)	57.34 (50–80)	58.27 (50–86)
Sex, n (%)
Female	1,224 (52.9%)	147 (50.6%)	1,371 (52.7%)
Male	1,086 (47.0%)	143 (49.3%)	1,229 (47.2%)
Race, n (%)
White	1,961 (84.8%)	183 (63.1%)	2,144 (82.4%)
Black or African American	257 (11.1%)	86 (29.6%)	343 (13.1%)
Other	97 (4.1%)	21 (7.2%)	118 (4.5%)

Table 2 Willingness of participants to undergo repeat screening with computed tomography colonography (CTC) and optical colonoscopy (OC)

Time interval	With bowel preparation					Without bowel preparation
	CTC		OC		P-value	CTC		OC		P-value
	N	%	N	%		N	%	N	%
Every year	368	16.1%	328	14.4%	0.001	1,133	49.8%	864	38.0%	<0.001
Every 3 years	1,026	45.0%	974	42.7%	0.003	1,694	74.5%	1,556	68.4%	<0.001
Every 5 years	1,809	79.3%	1,825	80.0%	0.368	2,055	90.4%	2,057	90.5%	0.946
Every 10 years	2,105	92.2%	2,204	96.6%	<0.001	2,154	94.7%	2,208	97.1%	<0.001
Never	143	6.3%	57	2.5%	<0.001	105	4.6%	56	2.5%	<0.001

Notes: Numbers in bold represent a comparison of intended adherence to recommended screening intervals (5 yearly CTC vs 10 yearly OC). P<0.001 for both comparisons: with and without bowel preparation.

Table 3 Discomfort experienced, comparison of actual discomfort compared with expectations, embarrassment experienced, and comparison of actual embarrassment compared with expectations for bowel preparation (BP), CT colonography (CTC), and optical colonoscopy (OC), and comparison of CTC and OC with respect to each parameter

	BP		CTC		OC		CTC vs OC	Respondents
	N	%	N	%	N	%	P-value*	Na
Any discomfort experienced	1,886	83.4%	1,838	81.3%	628	27.8%	<0.001	2,261
Discomfort worse than expected	426	19.0%	740	32.9%	112	5.0%	<0.001	2,247
Any embarrassment experienced	554	24.3%	971	42.5%	593	26.0%	<0.001	2,284
Embarrassment worse than expected	104	4.8%	185	8.5%	35	1.6%	<0.001	2,185

Notes:

* Exact P-values from McNemar’s test.

a Includes only cases with responses to all three modalities.

Table 4 Patient’s preference for the sex of the examiner by screening modality: computed tomography colonography (CTC) and optical colonoscopy (OC)

	Female participants					Male participants
	CTC		OC		P-value	CTC		OC		P-value
	N	%	N	%		N	%	N	%
Refuse any additional screening*	35	2.9%	14	1.2%	–	21	2.0%	7	0.7%	–
Prefer male examiner	3	0.2%	12	1.0%	0.022	90	8.4%	93	8.7%	0.766
Prefer female examiner	538	44.5%	293	24.3%	<0.001	78	7.3%	49	4.6%	<0.001
No preference	632	52.3%	889	73.6%	<0.001	880	82.3%	920	86.1%	<0.001

Notes:

* No P-value is shown for participants who planned to refuse additional screening, as these participants did not express a preference for the sex of the examiner. Exact P-values from McNemar’s test between tests on the proportion within category.

Table 5 Willingness of participants to undergo repeat screening correlated with procedural discomfort for optical colonoscopy (OC) and computed tomography colonography (CTC)

Variable	Value	Comparison with plans to adhere with both OC and CTC
		Plan to adhere with neither, OR (95% CI)	Plan to adhere with OC at 10 years,a OR (95% CI)	Plan to adhere with CTC at 5 years,a OR (95% CI)
Age	Per 10 year increaseb	1.78 (1.11–2.85)	1.19 (1.00–1.43)	1.30 (0.60–2.79)
Sex	Female vs male	2.46 (1.06–5.72)	1.85 (1.44–2.38)	1.49 (0.43–5.24)
Bowel preparation discomfort compared with expectations	Worse than expected vs better/same as expected	9.50 (4.41–20.48)	1.76 (1.32–2.33)	3.18 (0.95–10.70)
How much physical discomfort was experienced during CTC	Any vs none	3.78 (1.01–14.17)	1.39 (0.91–2.10)	0.47 (0.12–1.88)
CTC discomfort compared with expectations	Worse than expected vs better/same as expected	0.47 (0.19–1.17)	3.35 (2.58–4.33)	0.79 (0.17–3.79)
How much embarrassment was experienced during CTC	Any vs none	1.65 (0.75–3.64)	1.57 (1.22–2.01)	0.70 (0.18–2.66)
OC physical discomfort compared with expectations	Worse than expected vs better/same as expected	3.54 (1.38–9.05)	0.42 (0.20–0.87)	10.56 (2.94–37.92)
OC embarrassment compared with expectations	Worse than expected vs better/same as expected	18.49 (5.30–64.48)	0.42 (0.09–1.94)	7.56 (1.28–44.45)
Time spent away from usual activities per hour	Per hour	1.05 (1.00–1.11)	1.01 (0.98–1.03)	1.10 (1.02–1.18)
Biopsy	No vs yes	1.10 (0.52–2.34)	1.67 (1.29–2.18)	4.03 (0.84–19.28)

Notes: N=2,086 participants with data available for all covariates included in the analysis.

a Responses assume that each screening technique would require bowel preparation.

b Baseline age group (50 years). Bold values indicate odds ratios significantly different from 1.0.

Abbreviations: CI, confidence interval; OR, odds ratio.