Invitation strategies for colorectal cancer screening programmes: The impact of an advance notification letter.

Aim: To estimate the impact of an advance notification letter on participation in sigmoidoscopy (FS) and fecal immunochemical test (FIT) screening.

Methods: Eligible subjects, invited in 3 Italian population based programmes using FS and in 5 using FIT, were randomised (1:1:1), within GP, to: A) standard invitation letter; B) advance notification followed after 1month by the standard invitation; and C) B+indication to contact the general practitioner (GP) to get advice about the decision to be screened. We calculated the 9-month attendance and the incremental cost of each strategy. We conducted a phone survey to assess GP's utilization and predictors of participation.

Results: The advance notification was associated with a 20% increase in the attendance among 15,655 people invited for FS (B vs A - RR: 1.17, 95% CI: 1.10-1.25; C vs A - RR: 1.19, 95% CI: 1.12-1.27); the incremental cost ranged between 10 and 9 Euros. Participation in FIT screening (N=23,543) was increased only with simple pre-notification (B vs A - RR: 1.06, 95% CI: 1.02-1.10); the incremental cost was 22.5 Euros. GP consultation rate was not increased in group C.

Conclusions: An advance notification represents a cost-effective strategy to increase participation in FS screening; its impact on the response to FIT screening was limited.