Five-year experience of organized colorectal cancer screening in a Swedish population - increased compliance with age, female gender, and subsequent screening round.

OBJECTIVE: To evaluate compliance by age, gender, and screening round in the population based Stockholm/Gotland colorectal cancer screening programme.
METHODS: All individuals aged between 60 and 69 living in the counties of Stockholm and Gotland (Sweden) have, since 2008, successively been included in a colorectal cancer screening programme using biennial faecal occult blood tests (Hemoccult®). Personal invitations including test kits have been sent to home addresses, and individuals with a positive test result have been called to a defined clinic for an assessment colonoscopy. Descriptive statistics have been used to evaluate different aspects of compliance.
RESULTS: Over the five-year period 2008-2012, more than 200,000 individuals from nine different birth cohorts have been invited, with a compliance rate of approximately 60%, which increased by age, female gender, and subsequent screening round. In total, 4,300 individuals (2.1%) with positive tests were referred to assessment colonoscopy, where 213 colorectal cancers were diagnosed. The compliance with the follow-up colonoscopies varied by year, and ranged from 85.6-92.4%.
CONCLUSION: The strong organization of the programme contributed to a high compliance rate, that increased by screening round. The lower participation rate among men and among individuals at younger ages needs further attention.