A 25-year follow-up of a population screened with faecal occult blood test in Finland

Figures & data

Table I.  Number (n) of men and women invited to screening and person years (pyrs) of follow-up by attendance to screening and screening results among those attending over different periods of follow-up (0–1: up to 2 years, 2+: more than 2 years).

Gender, follow-up time	Screen positives	Screen negatives	Non-attenders	All invited
Men (n)	93	445	299	837
Follow-up (pyrs)
0–1	182	878	583	1 642
≥ 2	1 488	7 494	4 637	13 619
Total	1 670	8 371	5 220	15 261
Women (n)	137	552	259	948
Follow-up (pyrs)
0–1	272	1 100	512	1 883
≥ 2	2 735	10 780	4 940	18 455
Total	3 008	11 879	5 451	20 338
Both sexes (n)	230	997	558	1 785
Follow-up (pyrs)
0–1	454	1 977	1 095	3 526
≥ 2	4 223	18 274	9 576	32 073
Total	4 677	20 251	10 671	35 599

Table II.  Observed number of cases (Obs) and standardised incidence (SIR) and mortality (SMR) ratios with 95% confidence intervals (CI) for colorectal cancer in 1979–2004 among 1 785 persons invited to screening. Expected rates are based on the reference rates from the entire country of Finland.

	Incidence			Mortality
	Obs (N)	SIR	95% CI	Obs (N)	SMR	95% CI
Test positive
0–1*	4	21.2	5.76–54.15	–	0.00	0.00–41.81
2 + ^#	4	0.73	0.20–1.87	2	0.77	0.09–2.76
Total	8	1.41	0.61–2.78	2	0.74	0.09–2.67
Test negative
0–1	2	2.4	0.29–8.66	1	2.57	0.07–14.34
2 +	25	1.05	0.68–1.55	12	1.06	0.55–1.84
Total	27	1.1	0.72–1.59	13	1.11	0.59–1.89
Non-attendees
0–1	–	0.00	0.00–7.93	–	0.00	0.00–17.16
2 +	12	0.97	0.50–1.69	9	1.53	0.70–2.90
Total	12	0.94	0.48–1.63	9	1.48	0.67–2.80
All invited
0–1	6	4.03	1.48–8.77	1	1.45	0.04–8.05
2 +	41	0.98	0.71–1.33	23	1.16	0.73–1.73
Total	47	1.09	0.80–1.44	24	1.17	0.75–1.73

*0–1: Follow-up time up to 2 years.

^#2+: Follow-up time more than 2 years.