Even if there is no doubt that cancer prevention is very important, it cannot be assumed from the outset that cancer prevention measures will have the desired effect on the population. Data are needed to investigate which sections of the population use the measures, whether they are effective and, if so, how their effectiveness can be increased. Assessing effectiveness, in turn, requires not only data but also evaluation concepts allowing researchers to draw causal conclusions. In some cases, it is also necessary to measure advantages and disadvantages or to compare costs and benefits.

Data collection and evaluation therefore play an significant role in the “Model Region Bremen”. Different types of data are used:

The long-term goal is to reduce cancer incidence and mortality. Cancer registry data can be used for this purpose. The Bremen Cancer Registry has been recording new cases of cancer since 2001 with a completeness of over 95 percent and therefore has very high data quality. However, the effect of preventive measures usually only becomes apparent many years later. It is therefore necessary to include further indicators that can be measured earlier. For example, it can be assumed that changes in the use of preventive services, such as the HPV vaccination or colonoscopy, will have an impact on the future incidence of cancer in the population. In the “Model Region Bremen”, health insurance data is used to investigate changes in the use of preventive services. The GePaRD

database, which contains data since 2004 and covers more than 60 percent of Bremen's population, can be used for this purpose. In order to be able to examine indicators for which health insurance data contains little information, such as smoking, additional questionnaire data are collected in a sample at several measurement points. The questionnaires can also be used to record further indications of whether measures are having an effect, such as increased knowledge of prevention services or a change in attitude towards prevention. Structural indicators are also recorded, such as the physical activity program at elementary schools.

Data are collected and made available over the entire duration of the project in accordance with the FAIR principles in order to ensure transparency and reusability. Another central concern is the promotion of young scientists in the field of prevention research in order to ensure the continuity and further development of prevention efforts in Germany.