Socio-Territorial Inequities in the French National Breast Cancer Screening Programme-A Cross-Sectional Multilevel Study

Factors associated with deferral or non-performance of an organized breast cancer screening program during the COVID-19 pandemic in France

BACKGROUND

Delays in detection and treatment of breast cancer can lead to increased mortality. To date, participation in organized breast cancer screenings (OBCS) has been suboptimal worldwide. The objective of this study was to investigate the factors associated with deferral or non-performance of mammography during the COVID-19 pandemic for women who had previously participated in OBCS.

METHODS

A retrospective observational study was conducted on a cohort of 6282 women from the Aube Department of France, who were invited to an OBCS in 2020. Participants were divided into women who promptly underwent screening after receiving an invitation (between 22 and 25 months elapsed since the last mammogram), women who underwent late screening (≥26 months since the last mammogram), and those who were never screened. Data were collected from a self-reported questionnaire. Comparative and multivariable analyses modeling the probability of each type of attendance were performed using these data.

RESULTS

In total, 2301 women (aged 50-74 years) returned a valid questionnaire. Compared to women who promptly underwent mammography, non- and late-screening participants were younger, had less frequent gynecological follow-up and a less frequent history of colorectal cancer screening. Women with higher education status and those residing in socially disadvantaged areas were more likely to attend late.

CONCLUSION

The absence of regular gynecological follow-up and the absence of colorectal cancer screening were significant factors associated with deferral of or non-attendance at OBCS.

Functional forms of socio-territorial inequities in breast cancer screening - A French cross-sectional study using hierarchical generalised additive models

To reduce the breast cancer burden, the French National Organised Breast Cancer Screening Programme (FNOBCSP) was implemented in 2004. The recommended participation rate has never been achieved and socio-territorial inequities in participation have been reported on several occasions. We investigated the functional forms and consistency of the relationships between neighbourhood deprivation, travel time to the nearest accredited radiology centre and screening uptake. We used two-level hierarchical generalised additive models in 8 types of territories classified by socio-demographic and economic factors. The first level was 368,201 women aged 50-72 invited to the 2013-2014 screening campaign in metropolitan France. They were nested in 41 départements, the level of organisation of the FNOBCSP. The effect of travel time showed two main patterns: it was either linear (with participation decreasing as travel time increased) or participation first increased with increasing travel time to a peak around 5-15 min and decreased afterward. In nearly all types and départements, the probability of participation decreased linearly with increasing deprivation. Territorial inequities in participation were more context-dependent and complex than social inequities. Inequities in participation represent a loss of opportunity for individuals who already have the worst cancer outcomes. Evidence-based public health policies are needed to increase the effectiveness and equity of breast cancer screening.

Factors influencing participation in breast cancer screening in an urban setting. A study of organized and individual opportunistic screening among potentially active and retired women in the city of Nice

Participation in breast cancer screening in urban settings is poor. Identifying factors accounting for participation and non-participation is essential to target priority areas, tackle health inequalities and suggest innovative approaches. We studied organized and individual opportunistic participation in breast cancer screening within the 144 aggregated units for statistical information (Ilôts regroupés pour l'information statistique: IRIS) of the city of Nice from 2019 to 2021. In each IRIS was assessed a local human development index, among potentially active women aged 50 to 59 years and retired women aged 60 to 74 years. Modelling participation and non-participation in screening according to the IRIS units' socio-economical characteristics was performed using the SURE method (Seemingly Unrelated Regression Equations). Over a 2-year period, 24,396 breast screening tests were conducted (11,173 as organised screening, 13,223 as individual opportunistic screening). The local human development index was positively correlated with the two types of screening, respectively. Access to public transport facilitated participation. Managerial status was negatively correlated with organised screening. Single working women had a higher risk of non-participation. With regard to their socio-economic characteristics, screening rates were lower than expected in 16 IRIS units in the city of Nice. Local human development index, access to public transport, family and professional context appear to be associated with breast cancer screening in an urban setting. An innovative approach targeting these factors is called for to reduce health inequalities.

Evaluation of a mobile mammography unit: concepts and randomized cluster trial protocol of a population health intervention research to reduce breast cancer screening inequalities

BACKGROUND

Breast cancer is the leading cancer in women in France both in incidence and mortality. Organized breast cancer screening (OBCS) has been implemented nationwide since 2004, but the participation rate remains low (48%) and inequalities in participation have been reported. Facilities such as mobile mammography units could be effective to increase participation in OBCS and reduce inequalities, especially areas underserved in screening. Our main objective is to evaluate the impact of a mobile unit and to establish how it could be used to tackle territorial inequalities in OBCS participation.

METHODS

A collaborative project will be conducted as a randomized controlled cluster trial in 2022-2024 in remote areas of four French departments. Small geographic areas were constructed by clustering women eligible to OBCS, according to distance to the nearest radiology centre, until an expected sample of eligible women was attained, as determined by logistic and financial constraints. Intervention areas were then selected by randomization in parallel groups. The main intervention is to propose an appointment at the mobile unit in addition to current OBCS in these remote areas according to the principle of proportionate universalism. A few weeks before the intervention, OBCS will be promoted with a specific information campaign and corresponding tools, applying the principle of multilevel, intersectoral and community empowerment to tackle inequalities.

DISCUSSION

This randomized controlled trial will provide a high level of evidence in assessing the effects of mobile unit on participation and inequalities. Contextual factors impacting the intervention will be a key focus in this evaluation. Quantitative analyses will be complemented by qualitative analyses to investigate the causal mechanisms affecting the effectiveness of the intervention and to establish how the findings can be applied at national level.

TRIAL REGISTRATION

Registered on ClinicalTrials.gov, December 21, 2021: NCT05164874 .

Can an Ecological Index of Deprivation Be Used at the Country Level? The Case of the French Version of the European Deprivation Index (F-EDI)

Most ecological indices of deprivation are constructed from census data at the national level, which raises questions about the relevance of their use, and their comparability across a country. We aimed to determine whether a national index can account for deprivation regardless of location characteristics. In Metropolitan France, 43,853 residential census block groups (IRIS) were divided into eight area types based on quality of life. We calculated score deprivation for each IRIS using the French version of the European Deprivation Index (F-EDI). We decomposed the score by calculating the contribution of each of its components by area type, and we assessed the impact of removing each component and recalculating the weights on the identification of deprived IRIS. The set of components most contributing to the score changed according to the area type, but the identification of deprived IRIS remained stable regardless of the component removed for recalculating the score. Not all components of the F-EDI are markers of deprivation according to location characteristics, but the multidimensional nature of the index ensures its robustness. Further research is needed to examine the limitations of using these indices depending on the purpose of the study, particularly in relation to the geographical grid used to calculate deprivation scores.