Table 2

Screened cohort characteristics

	Patients with no polyps		Patients with small polyps		Patients with other findings		Total patients
	N=883	Per cent	N=567	Per cent	N=238	Per cent	N=1688	Per cent	p Value*
Polyps
No polyps	883	100.0	0	0.0	0	0.0	883	52.3	<0.001
Only small polyps (<10 mm)	0	0.0	567	100.0	0	0.0	567	33.6
Small and large polyps	0	0.0	0	0.0	150	63.0	150	8.9
Only large polyps	0	0.0	0	0.0	58	24.4	58	3.4
Polyps and other findings	0	0.0	0	0.0	16	6.7	16	0.9
No polyps, cancer suspected	0	0.0	0	0.0	14	5.9	14	0.8
Incomplete colonoscopy	54	6.1	1	0.2	9	3.8	64	3.8	<0.001
Discomfort-tortuosity related	32	59.3	0	0.0	7	77.8	39	60.9	0.011
Preparation-related	21	38.9	0	0.0	1	11.1	22	34.4
Other	1	1.9	1	100.0	1	11.1	3	4.7
Site
County Durham and Darlington	260	29.4	164	28.9	61	25.6	485	28.7	<0.001
North Cumbria	38	4.3	28	4.9	9	3.8	75	4.4
North Tees and Hartlepool	166	18.8	156	27.5	88	37.0	410	24.3
Northumbria	70	7.9	37	6.5	24	10.1	131	7.8
South Tees	193	21.9	65	11.5	20	8.4	278	16.5
South Tyneside	156	17.7	117	20.6	36	15.1	309	18.3
Age (years); median, IQR	62.2	49.8–68.3	65.9	60.0–70.4	66.7	62.3–72.4	64.3	55.0–70.2	<0.001
Gender
Female	488	55.3	218	38.4	86	36.1	792	46.9	<0.001
Male	394	44.7	349	61.6	152	63.9	895	53.1
Ethnicity
White—British	866	99.3	560	98.8	235	99.6	1661	99.2	0.218
Asian or Asian British	5	0.6	2	0.4	0	0.0	7	0.4
Black or Black British	0	0.0	1	0.2	0	0.0	1	0.1
Chinese or other ethnic groups	1	0.1	1	0.2	1	0.4	3	0.2
White—other	0	0.0	3	0.5	0	0.0	3	0.2
Smoking
Current smoker	142	16.3	122	21.5	40	16.9	304	18.2	<0.001
Previous smoker	321	36.9	250	44.1	113	47.7	684	40.9
Never smoked	407	46.8	195	34.4	84	35.4	686	41.0
Alcohol use	522	60.1	365	64.5	166	69.7	1053	63.0	0.016
Units/week (users); median, IQR	9.0	4.0–16.0	14.0	6.0–23.5	14.0	6.0–27.0	11.0	5.0–20.0	<0.001
Taking any regular medication	720	81.5	499	88.0	198	83.5	1417	84.0	0.004
Taking an NSAID	81	11.2	38	7.6	11	5.5	130	9.1	0.018
Taking a statin	245	33.8	260	52.1	114	56.7	619	43.4	<0.001
Taking aspirin	138	19.1	122	24.4	50	25.0	310	21.8	0.040
Primary reason for colonoscopy
BCSP	162	18.3	190	33.5	124	52.1	476	28.2	<0.001
Change in bowel habit	276	31.3	132	23.3	37	15.5	445	26.4	<0.001
Surveillance procedure	122	13.8	137	24.2	34	14.3	293	17.4	<0.001
Per-rectal bleeding	130	14.7	59	10.4	28	11.8	217	12.9	0.050
Iron-deficiency anaemia	122	13.8	60	10.6	13	5.5	195	11.6	0.001
Other	122	13.8	19	3.4	22	9.2	163	9.7	<0.001
Abdominal pain	93	10.5	32	5.6	8	3.4	133	7.9	<0.001
Weight loss	34	3.9	23	4.1	5	2.1	62	3.7	0.389
Family history	30	3.4	25	4.4	5	2.1	60	3.6	0.274
Abnormal imaging	9	1.0	2	0.4	2	0.8	13	0.8	0.396
Previous colonoscopy, within 10y	336	38.1	272	48.0	79	33.3	687	40.7	<0.001
Previous colorectal cancer (CRC)	32	3.6	16	2.8	3	1.3	51	3.0	0.161
Previous CRC (years); median, IQR	5.5	3.9–6.8	4.8	1.6–10.2	10.7	4.8–63.8	5.5	3.3–9.6	0.441
Family history of CRC†	181	20.5	120	21.2	40	16.8	341	20.2	0.352

*Three-way Fisher’s exact test for counts, three-way Kruskal–Wallis test for continuous measures.
†A: Two or more first-degree relatives or one first-degree relative <45 years old; B: one first-degree relative >45 years old; C: one or more second-degree or third-degree relative(s); D: none. BCSP, Bowel Cancer Screening Programme; NSAID, non-steroidal anti-inflammatory drug.