Are you ready for the xShare Button?



The  xShare Yellow Button will allow us to share our health data safely and with trust in the European Electronic Health Records Exchange Format (EHRxF) as noted in the upcoming European Health Data Space (EHDS) regulation.


But why do we call it a YELLOW button?

The inspiration for the yellow button came from a flower which is growing all over Europe: the buttercup. 

The yellow colour of the buttercup is due to pigments which absorb blue and green light

The outermost layer of the petals, the epidermis, is made up of flat cells containing the pigments. It is separated from the endodermis (a deeper layer devoid of pigments) by a thin air gap. Incident light is partly reflected and transmitted on each surface: the upper surface of the epidermis, the lower surface of the epidermis and the surface of the endodermis. 

The epidermis reflects light in a preferred direction while the endodermis, which has a strong reflective power, diffuses light outwards in all directions. As the blue and green components of light are absorbed by the pigments, the light reflected by the surface of the epidermis is slightly dominated by yellow, while the light reflected deeper, more filtered by the pigments, comes out intensely yellow. In addition, the concave shape of the petals concentrates the yellow light on a small area.

The ambition of the xShare YELLOW button, developed in the Horizon Europe xShare project, is likewise – to use the European Electronic Health Record Exchange Format (EEHRxF) formats as the foundation (endoderm) which will allow to use those data in all critical information domains and create NEW value (light), allowing extended use of FAIR data in the clinical domain but also connecting closely primary and secondary use of data.

All the stars on the European flagship are also yellow while the blue background is also a reference to the blue button which is deployed in the USA. Like for the butternut, the blue  European “pigment” of the EEHRxF is the condition to create this intense yellow colour which can then be reflected in a large number of business use cases.

The xShare Yellow button IS thus the entry door to a collaboration  between domains and the creation of a dynamic and transparent value-based ecosystem in the hands of the citizen and the patient.


Written by Luc Nicolas, ICT for Health Expert at EHTEL

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