Making the BEST decision-the BESTa project development, implementation and evaluation of a digital Decision Aid in Swedish cancer screening programmes- a description of a research project.

BACKGROUND: Sweden has a long tradition of organized national population-based screening programmes. Participation rates differ between programmes and regions, being relatively high in some groups, but lower in others. To ensure an equity perspective on screening, it is desirable that individuals make an informed decision based on knowledge rather than ignorance, misconceptions, or fear. Decision Aids (DAs) are set to deliver information about different healthcare options and help individuals to visualize the values associated with each available option. DAs are not intended to guide individuals to choose one option over another. The advantage of an individual Decision Aid (iDA) is that individuals gain knowledge about cancer and screening by accessing one webpage with the possibility to communicate with health professionals and thereafter make their decision regarding participation. The objective is therefore to develop, implement and evaluate a digital iDA for individuals invited to cancer screening in Sweden. METHODS: This study encompasses a process-, implementation-, and outcome evaluation. Multiple methods will be applied including focus group discussions, individual interviews and the usage of the think aloud technique and self-reported questionnaire data. The project is based on The International Patient Decision Aid Standards (IPDAS) framework and the proposed model development process for DAs. Individuals aged 23-74, including women (the cervical-, breast- and CRC screening module) and men (the CRC screening module), will be included in the developmental process. Efforts will be made to recruit participants with self-reported physical and mental limitations, individuals without a permanent residence and ethnic minorities. DISCUSSION: To the best of our knowledge, the present study is the first attempt aimed at developing an iDA for use in the Swedish context. The iDA is intended to facilitate shared decision making about participation in screening. Furthermore, the iDA is expected to increase knowledge and raise awareness about cancer and cancer screening. PATIENT OR PUBLIC CONTRIBUTION: Lay people are involved throughout the whole development and implementation process of the digital DA. TRIAL REGISTRATION: NCT05512260.

Gender-specific cut-offs in colorectal cancer screening with FIT: Increased compliance and equal positivity rate.

OBJECTIVE: Using quantitative Faecal Immunochemical Test (FIT) in colorectal cancer screening enables adjustment of the cut-off for a positive test. As men have higher stool blood levels and higher prevalence of colorectal neoplasia, different cut-off levels can be chosen for men and women. We evaluated participation and positivity rates switching from guaiac-based faecal occult blood test (gFOBT) (Hemoccult®) to FIT (OC-Sensor), using gender-specific cut-offs. METHODS: The colorectal cancer screening programme of Stockholm-Gotland, Sweden, started in 2008 and invited individuals aged 60-69 to biennial testing using gFOBT. From 1 October 2015 the test was switched to FIT, with positivity cut-offs of 40 (200) and 80 (400) µg Hb/g (ng/mL) faeces for women and men, respectively. The first year was evaluated for compliance and positivity, number of reminders and incorrect/inadequate tests, compared with gFOBT in the preceding 12-month period. RESULTS: There were 127,030 and 87,269 individuals invited to screening with gFOBT and FIT, respectively. The change of test increased overall participation by 11.9% (95% confidence interval 11.5%-12.3%) from 56.5% to 68.4% ( p < 0.001). The increase was larger in men (14.3%) than women (9.7%), and in those aged 60-64 (14.2%) than those aged 65-69 (8.7%). The positivity rate was 2.6% in women and 2.5% in men. There was a lower rate of reminders and incorrect/inadequate tests with FIT. CONCLUSIONS: Within a well-organised colorectal cancer screening programme, changing the test from gFOBT to FIT markedly increased participation, especially among men, and in the younger age group. With a lower cut-off in women than men, the positivity rate was similar.

Initial participation as a predictor for continuous participation in population-based colorectal cancer screening.

OBJECTIVES: To assess patterns and probabilities of participation in multiple rounds of colorectal cancer screening. METHODS: All individuals who were invited to participate in population-based colorectal cancer screening in the Stockholm-Gotland region in Sweden between 1 January 2008 and 30 September 2015 were included in the study. Guaiac-based faecal occult blood testing was used. All individuals invited to the three first consecutive screening rounds were included in the analysis. RESULTS: There were 346,168 individuals eligible for invitation to screening. The average participation rate during the follow-up period was 60%. Eligible individuals could be invited 1-4 times, depending on age at first invitation. Of 48,959 individuals invited to the three first consecutive rounds of screening, 71% participated at least once, and 50% participated in all three rounds. Participation at first invitation was a predictor for participation in subsequent rounds, and the likelihood of continuous participation following participation in the first round was 84%. Of those who attended the first and second rounds, 93% also participated in the third round. Similar patterns of consistency were seen among non-participants. For individuals not participating in the first screening round, the likelihood of consistent non-participation was 71. CONCLUSIONS: Participation in the first round of screening is a strong predictor for participation in subsequent rounds. Therefore, reducing barriers for initial participation is a key for achieving consistent participation over several rounds in organized colorectal cancer screening programmes.