Inherited platelet disorders (IPD) are a heterogeneous group of rare bleeding diseases. This group is:

• Associated with a reduction of platelet number and/or function
• Characterized by a bleeding tendency ranging from mild to severe

Despite recent significant breakthroughs, IPDs are largely neglected because they're rare and generally considered benign. For this reason, they remain under-diagnosed and their prevalence is still unknown.

Rare disease registries are a way of systematically collecting of data on the diagnosis and management of patients. They allow us to:

• Estimate the prevalence of a disorder
• Get deeper insight into a disorder's prognosis

The potential result of this is that we can improve both diagnosis and management. However, the few existing registries on IPD are set up as independent studies and do not interoperate with one another.

The primary objective of this EHA-SWG-initiated small research project is to establish the first European registry on IPDs (ERIPD). This will:

• Represent the first collection of clinical, laboratory, and genetic data of a large cohort of patients with different forms of IPD from different geographical areas in Europe
• Provide insights into the real prevalence of these disorders in Europe
• Help to address unmet needs regarding their impact on patients' lives and healthcare systems