Open Access

Large-scale, population-based cohort studies gather a range of data from participants over extended periods of time with the goal of providing researchers with information regarding the health status, prevalence of disease, and risk factors in a regional population. Examinations conducted in the context of population-based studies include imaging and laboratory testing and may yield abnormal results, also called incidental findings. According to predetermined disclosure policies, incidental findings may be disclosed to study participants. Evidence shows that the disclosure of incidental findings results in medical follow-up as research participants and their physicians seek to clarify the significance of findings. This work examined the effect of disclosing incidental findings from whole-body MRI (wb-MRI) on the frequency and organ system of biopsies in participants in the Study of Health in Pomerania (SHIP), a population-based cohort study in Mecklenburg-West Pomerania. As most of the incidental wb-MRI findings involved unclear masses and lesions, we hypothesized that the disclosure of wb-MRI findings would lead to an increase in diagnostic biopsies. Based on current data showing that the outcomes of incidental imaging findings are frequently clinically irrelevant, we further hypothesized that an increase in biopsies would not translate to a clinically relevant increase in diagnoses of malignancies. We also took disclosed laboratory findings into account, as they were disclosed to all SHIP participants and may play a role in the decision to pursue a biopsy. We found that the rate of biopsies increased after participation in SHIP and disclosure of incidental MRI and laboratory findings. Overall, most biopsies showed nonmalignant findings, indicating likely overdiagnosis and overtesting resulting from the disclosure of incidental findings in our cohort. However, subgroups of participants with disclosed MRI findings had a higher proportion of biopsies revealing premalignant or malignant diagnoses after SHIP, indicating that the applied decision rules for disclosure of MRI findings led to the identification of individuals with an elevated risk for premalignant or malignant diagnoses. The clinical relevance of these diagnoses is unclear and overdiagnosis cannot be ruled out. In summary, we recommend more restrictive disclosure policies for incidental imaging findings in research to protect research participants from overtesting and to reduce bias. Further studies regarding the long-term morbidity and mortality of participants are needed to better understand the therapeutic impact of the disclosure of incidental wb-MRI findings in the research setting.