Trajectories and individual determinants of regular cancer screening use over a long period based on data from the French E3N cohort.

Despite several incentive policies for cancer screenings over the last two decades, the overall and regular use of cancer screenings remains insufficient in France. While the individual determinants of cancer screening uptake have been fairly well studied, the literature has rarely focused on the regularity of screening uptake, which is key to early cancer detection. We aimed to address this issue by studying cancer screening behaviors over 15 years, emphasizing the regularity and diversity of use. Using data from 40,021 women in the French E3N cohort, we studied the individual trajectories of screenings for breast, colorectal and cervical cancer between 2000 and 2014. We employed optimal matching methods to identify typical behaviors of use for each cancer screening. Then, we determined the associations between the identified behavior screening patterns for the different cancer screenings and, finally, assessed the associated individual determinants with logistical and multinomial models. We found that screening behaviors were fairly stable over time, with few typical screening patterns for each cancer. Overall, once a woman starts screening, she continues, and once she stops, she no longer returns. Cancer screening behaviors appear consistent; in particular, insufficient use of mammography appears to be associated with long-term nonuse of other cancer screenings. Factors associated with low or nonuse of screening are overall common between cancer screenings and are similar to those identified in the literature of screening use at a single point in time. Ultimately, these barriers prevent some women from entering a screening process in the long run, ultimately reinforcing social inequalities in health. Targeting women with insufficient mammography uptake may reach women outside of cancer screening settings more generally and, thus, both increase the overall uptake of cancer screening and reduce social inequalities in cancer screening.