Introduction of an organised programme and social inequalities in mammography screening: a study based on a 22-year-old population in Geneva, Switzerland
José Luis Sandoval, Jean-Marc Theler, Stéphane Cullati, Christine Bouchardy, Orly Manor, Jean-Michel Gaspoz, Idris Guessous.
Introduction of an organised programme and social inequalities in mammography screening: A 22-year population-based study in Geneva, Switzerland., Preventive Medicine, October 2017, doi: 10.1016/j.ypmed.2017.07.025.
Abstract
Background: In developed countries, mortality from breast cancer has decreased in recent decades, at least partly due to the advent of mammography screening. One of the aims of prevention programmes is to increase participation and reduce social inequalities in access to screening.
Objectives: We sought to characterise changes in socioeconomic disparities in mammography screening before and after the introduction of a prevention programme in Geneva, Switzerland.
Setting: We included 5345 women, aged 50 to 74, with no history of breast cancer, who participated in the cross-sectional Bus Santé study between 1992 and 2014.
Methods: Outcome criteria were 1) never had a mammogram (1992-2014) and 2) never had a mammogram or not screened in the two years prior to the survey (subgroup analysis, 2007-2014). The level of education was divided into three groups (primary, secondary and tertiary) and the period into two (before/after the introduction of a screening programme in 1999). We calculated measures of relative and absolute change, including relative (RII) and slope (SII) indices of social inequality, adjusted for age and nationality. We compared the prevalence of screening before and after the implementation of the screening programme using Poisson models.
Results: The proportion of unscreened women decreased over the study period, from 30.5% to 3.6%. Less educated women were more often not screened (RII=2.39, p<0.001; SII=0.10, p<0.001). Organised screening reduced the proportion of unscreened women regardless of education level (prevalence ratio before vs after=4.41, p<0.001), but absolute and relative inequalities persisted (RII=2.11, p=0.01; SII=0.04, p=0.01).
Conclusion: The introduction of a prevention programme increased women's adherence to mammography screening, but did not eliminate social disparities in participation in screening.