Short summary

The overall purpose of this study, is to investigate if there is equal access to and use of diagnostic follow-up procedures after cancer screening in Denmark. We use national health registers to follow screened residents for at least five years and evaluate their adherence to follow-up guidelines and associations with social position and organizational factors. Furthermore, associations between derived resource use and social position will be analysed.

Rationale

In Denmark, organized screening programmes for breast, cervical and colorectal cancer has been in place for several years. The programmes are monitored through national screening statistics and databases. Very little has been known about the follow-up pathways from an abnormal screening result until a diagnosis or resolution. Earlier studies and programme statistics have only reported on the first step of the follow-up pathway or certain parts of the pathway and not the follow-up in its entirety. Recently, we published evidence of these follow-up pathways in detail for the breast and cervical cancer screening programmes. Our results showed large variation between the two programmes in how follow-up recommendations are complied to and how many diagnostic tests and procedures they employ. While most women had the recommended follow-up after breast cancer screening, the follow-up pathways after cervical screening suffered from very poor adherence, with geographical variations and differences between providers, i.e. private and public health care sites.

These health care pathways following cancer screening are somewhat separated from the screening offer but also from the clinical cancer care pathways. They often involve several health care providers and several levels. The follow-up pathways and whether they comply with the recommendations has so far not received a lot of attention. Whether the reasons behind or findings should be found at the individual level, e.g. in women's pre-requisites, at a structural organizational level or a combination, remains to be studied.

Social inequality in health seems to be growing and a challenge that several Danish health organizations address. Previous research provide evidence that socioeconomic position affects the survival of several cancer diagnoses. Furthermore, referral and attendance to cancer rehabilitation is negatively associated with low socioeconomic position.

In the context of cancer screening research, we have solid evidence that people with lower socioeconomic position participate less than people with higher socioeconomic position (17, 18). Studies suggest that this might also be the case during follow-up (19). However, the studies are not very informative in assessing the entire follow-up pathways or the different nuances in follow-up adherence such as whether they receive insufficient care or overtreatment. The studies also did not assess how organizational factors may affect potential inequalities. With this study, we will contribute to the existing research on inequity in cancer prevention and care by studying potential interactions between structural socioeconomic and organizational factors in the follow-up after cancer screening. Identifying an effect of the interactions between certain socioeconomic characteristics and the health care provider's characteristics on the risk of non-adherence to follow-up care, will clarify existing knowledge of social inequity in cancer screening and follow-up care. This is important in order to make targeted interventions aiming to improve the adherence to specific parts of the follow-up pathways in specific population groups.

Description of the cohort

The study is designed as a register-based cohort study including men and women with abnormal screening results after participating in breast, cervical or colorectal cancer screening in the period from 2014 until end of 2017 and with five years follow-up until 2022 to be able to assess the complete follow-up pathways. The project is divided into three sub-studies including the following three populations: - Women aged 23-59 years with abnormal cytological cervical samples and 60-64 years old women with positive HPV samples as part of organized cervical cancer screening. - Women aged 50-69 years who attended mammography screening in the period and had an abnormal screening mammogram. - Men and women aged 50-74 years who delivered a positive FIT test as part of the first four years of colorectal cancer screening. We have previously developed a framework of how to map the follow-up pathways for all residents with abnormal screening results. We will use this to assess whether men and women adhere to the recommended current national published guidelines throughout the entire follow-up pathways depending on the screening diagnosis and recommendation for follow-up.

Data and biological material

To analyse the association between socioeconomic position and adherence to follow-up, we will include detailed information from Statistics Denmark using their pre-determined categories of socio-economic characteristics i.e. information of education, occupation, civil status and ethnicity. Based on the classifications, ethnicity is categorised into Western and non-Western origin and civil status into married/registered partnership, cohabitating or living alone. Occupation is categorized as self-employed, chief executive, employed, social welfare recipient, retired or other. Educational levels are low (≤10 years), middle (11-15 years) or higher education (≥ 15 years). In the second part of the analysis, we will study how certain organizational factors potentially could affect adherence to follow-up among residents with lower social positions. From the National Patient Register, we will include information on hospital size, provider level (public/private) and geographical placement. From the National Health Service Register and the Provider registry, we will include information of practice size, age and gender of provider, number of patients per practice, urban/rural placement and level of interprofessionality among general practices and private practicing gynaecologists and surgeons.

Collaborating researchers and departments

Department of Data, Innovation and Research, Vejle Hospital

• Associate professor Sisse Helle Njor

Steno Diabetes Center, Department of Clinical Medicine, Aarhus University

• Associate professor Tinne Laurberg