Developing Primary Care Algorithms for Early Identification of Young Women with von Willebrand Disease - PROJECT SUMMARY / ABSTRACT Bleeding disorders in women remain under-recognized and under-treated. Although expert guidelines recommend screening adolescents with heavy menstrual bleeding (HMB) for von Willebrand Disease (VWD), our team has identified that under-screening remains widespread. Recent advances in VWD screening include the validation of bleeding assessment tools (BATs), with the International Society of Thrombosis and Haemostasis BAT (ISTH-BAT) serving as the current standard. However, the reference range of the ISTH-BAT score for young women is unknown, and there is a lack of research examining the accuracy of BATs in primary care settings. Our team has also shown that iron deficiency is common in young women with HMB, and while point-of-care (POC) ferritin technology is newly available, its utility as a screening tool for VWD in women with HMB has not been evaluated. The primary objective of this R01 application is to compare the validity of three screening strategies to identify young women with HMB who have an underlying diagnosis of VWD: 1) BAT, 2) POC ferritin, and 3) combined BAT + POC ferritin. Our rationale for this research is that early diagnosis of VWD in women with HMB can alleviate morbidity and mortality by enabling health care providers to optimally manage HMB and develop care plans for future surgical events and childbirth, thus decreasing the incidence and severity of bleeding events. Building upon our expertise in BATs, VWD, and past success in the recruitment of young women for HMB studies, we will achieve our objectives through the following specific aims: 1) establish the reference range of the ISTH-BAT in a general population of post-menarchal females 10-20 years of age, 2) compare the validity of the following screening tools (BAT, ferritin, BAT+ferritin) in identifying young women with HMB and underlying VWD, and 3) assess the feasibility of a primary care VWD screening algorithm, as well as patient, caregiver, and clinician experience. Our study population will include ~1,800 post-menarchal females presenting for care at five primary care clinics. Participants will complete the BAT and POC ferritin during their clinical visit. Those meeting the study definition of HMB will undergo laboratory testing for VWD. We will collect feasibility measurements (i.e., participation rate, time to complete screening algorithm). We will perform semi- structured interviews with a subset of participants, parents, and health care providers to explore domains such as the acceptability, appropriateness, and impact of VWD screening on clinic workflows. Our central hypothesis is that BAT + ferritin will have higher specificity for VWD than BAT or POC ferritin alone. Our project is innovative because it shifts the study of young women with bleeding disorders from the status quo of specialized hematology centers to the primary care settings in which young women with HMB initially present. The studies proposed here will serve as a foundation for comparing a VWD primary care screening algorithm against standard of care in a prospective clinical trial to measure its effect on health outcomes such as initiation of HMB and iron deficiency treatment, specialty referral, laboratory screening for underlying bleeding disorders, and patient quality of life.