Differences in diagnostic activity in general practice and findings for individuals invited to the danish screening programme for colorectal cancer: a population-based cohort study

Figures & data

Figure 1. Flowchart of the study population. The number of CRC diagnoses for each subgroup is stated for the year following the screening invitation.

Figure 2. (A-C) Mean rates of daytime face-to-face consultations and haemoglobin measurements for subgroups in the screening for CRC. Estimates are for 3-month intervals, 12 months preceding invitation to screening. The upper graph illustrates the unadjusted average consultation rate for individuals in subgroups. The lower graph illustrates the IRRs for comparison of subgroups adjusted for age, gender, country of origin, educational level, labour market affiliation, marital status, CCI score, prescriptions of medicine against haemorrhoids, NSAIDs, acetylsalicylic acids and anticoagulant drugs.

Table 1. Characteristics of individuals included in the analyses on diagnostic activity.

	Participants		Non-participants		Positive FIT		Negative FIT		Colorectal cancer		No colorectal cancer
	n	%	n	%	n	%	n	%	n	%	n	%
Total	245,299		130,899		16,206		229,093		907		13,955
Gender†
Male	113,632	46.3	71,912	54.9	9,083	56.1	104,549	45.6	538	59.3	7,781	55.8
Female	131,663	53.7	58,978	45.1	7,123	43.9	124,540	54.4	369	40.7	6,174	44.2
Age (years)
50-54	83,138	33.9	54,306	41.5	3,467	21.4	79,671	34.8	87	9.6	3,154	22.6
55-59	35,887	14.6	18,727	14.3	1.910	11.8	33,977	14.8	77	8.5	1,695	12.2
60-64	35,599	14.5	16,003	12.2	2,392	14.7	33.207	14.5	126	13.9	2,102	15.1
65-69	39,734	16.2	15,903	12.2	3,254	20.1	36,480	15.9	198	21.8	2,794	20.0
70-74	50,941	20.8	25,960	19.8	5,183	32.0	45,758	20.0	419	46.2	4,210	30.2
Country of origin
Danish	229,909	93.7	118,402	90.5	15,360	94.8	214,549	93.7	881	97.1	13,233	94.8
Immigrant (western)	7,569	3.1	5,486	4.2	468	2.9	7,101	3.1	19	2.1	385	2.8
Immigrant (non-western)	7,821	3.2	7,011	5.3	378	2.3	7,443	3.3	7	0.8	337	2.4
Educational level
Basic	65,204	26.6	46,202	35.3	5,048	31,1	60,156	26.3	295	32.5	4,258	30.5
Medium	121,980	49.7	59,217	45.2	8,273	51.1	113,707	49.6	467	51.5	7,143	51.2
High	58,115	23.7	25,480	19.5	2,885	17.8	55,230	24.1	145	16.0	2,554	18.3
Labour marked affiliation†
Working	136,066	55.5	66,792	51.0	6,576	40.6	129,490	56.5	310	34.2	5,924	42.5
Unemployed	37,298	15.2	29,619	22.6	2,691	16.6	34,607	15.1	88	9.7	2,324	16.7
Pension	71,931	29.3	34,479	26.4	6,939	42.8	64,992	28.4	509	56.1	5,707	40.9
Marital status†
Married/cohabiting	184,196	75.1	77,840	59.5	11,526	71.1	172,670	75.4	665	73.3	10,099	72.4
Single/living alone	61,099	24.9	53,050	40.5	4,680	28.9	56,419	24.6	242	26.7	3,856	27.6
Charlson Comorbidity Index
Low	186,198	75.9	95.442	72.9	10,591	65.4	175,607	76.7	614	67.7	9,272	66.4
Moderate	47,443	19.3	26,000	19.9	4,109	25.3	43,334	18.9	226	24.9	3,477	24.9
Severe	11,658	4.8	9,457	7.2	1,506	9.3	10,152	4.4	67	7.4	1,206	8.6
Prescription for medicine against haemorrhoids
No	236,184	96.3	127,613	97.5	15,521	95.8	220,663	96.3	870	95.9	13,396	96.0
Yes	9,115	3.7	3,286	2.5	685	4.2	8,430	3.7	37	4.1	559	4.0
Prescription for NSAID
No	194,067	79.1	105,945	80.9	12,479	77.0	181,588	79.3	743	81.9	10,691	76.6
Yes	51,232	20.9	24,954	19.1	3,727	23.0	47,505	20.7	164	18.1	3,264	23.4
Prescription for acetylsalicylic acids
No	214,396	87.4	114,097	87.2	12,942	79.9	201,454	87.9	729	80.4	11,214	80.4
Yes	30,903	12.6	16,802	12.8	3,264	20.1	27,639	12.1	178	19.6	2,741	19.6
Prescription for anticoagulant drugs
No	228,729	93.2	120,686	92,2	13,955	86.1	214,774	93.8	803	88.5	12,091	86.6
Yes	16,570	6.8	10,213	7.8	2,251	13.9	14,319	6.2	104	11.5	1,864	13.4

† Information on gender, labour marked affiliation and marital status were missing for 13 individuals.

Figure 3. Cumulative incidence of CRC among individuals invited for screening participation, one year following invitation. Incidence was stratified for screening participation. In total, 907 CRCs were diagnosed in the screening (red curve) and 308 CRCs were diagnosed outside the screening (blue and green curves).

Table 2. Characteristics for individuals diagnosed with CRC in the year following the screening invitation.

	Participants diagnosed with CRC in the screening		Participants diagnosed with CRC outside the screening		Non-participants diagnosed with CRC
	n	%	n	%	n	%
Total	907		69		239
Gender
Male	538	59.3	35	50.7	147	61.5
Female	369	40.7	34	49.3	92	38.8
Age (years)
50-54	87	9.6	10	14.5	28	11.7
55-59	77	8.5	0	–	14	5.9
60-64	126	13.9	9	13.0	47	19.7
65-69	198	21.8	22	31.9	38	15.9
70-74	419	46.2	28	40.6	112	46.8
Country of origin
Danish	881	97.1	66	95.7	230	96.2
Immigrant (western)	19	2.1	3	4.3	NA	–
Immigrant (non-western)	7	0.8	0	–	NA	–
Educational level
Basic	295	32.5	24	34.8	84	35.1
Medium	467	51.5	35	50.7	109	45.6
High	145	16.0	10	14.5	46	19.3
Labour market affiliation
Working	310	34.2	21	36.2	75	31.4
Unemployed	88	9.7	8	13.8	41	17.1
Pension	509	56.1	29	50.0	123	51.5
Marital status
Married/cohabiting	665	73.3	53	76.8	141	59.0
Single/living alone	242	26.7	16	23.2	98	41.0
Charlson Comorbidity Index
Low	614	67.7	45	65.2	144	60.3
Moderate	226	24.9	17	24.6	60	25.1
Severe	67	7.4	7	10.1	35	14.6
UICC stage
I	246	27.1	24	10.0	10	14.5
II	160	17.6	40	16.7	12	17.4
III	171	18.9	51	21.3	13	18.8
IV	51	5.6	46	19.3	13	18.9
Unknown	279	30.8	78	32.7	21	30.4