TECHNICAL NOTE ElVisML: an open data format for the exchange and storage of electrophysiological data in ophthalmology Torsten Strasser . Tobias Peters . Herbert Ja ¨gle . Eberhart Zrenner Received: 25 April 2017 / Accepted: 2 November 2017 Ó Springer-Verlag GmbH Germany, part of Springer Nature 2017 Abstract Purpose The ISCEV standards and recommenda- tions for electrophysiological recordings in ophthal- mology define a set of protocols with stimulus parameters, acquisition settings, and recording condi- tions, to unify the data and enable comparability of results across centers. Up to now, however, there are no standards to define the storage and exchange of such electrophysiological recordings. The aim of this study was to develop an open standard data format for the exchange and storage of visual electrophysiolog- ical data (ElVisML). Methods We first surveyed existing data formats for biomedical signals and examined their suitability for electrophysiological data in ophthalmology. We then compared the suitability of text-based and binary formats, as well as encoding in Extensible Markup Language (XML) and character/comma-separated values. Results The results of the methodological consider- ation led to the development of ElVisML with an XML-encoded text-based format. This allows refer- ential integrity, extensibility, the storing of accompa- nying units, as well as ensuring confidentiality and integrity of the data. A visualization of ElVisML documents (ElVisWeb) has additionally been devel- oped, which facilitates the exchange of recordings on mailing lists and allows open access to data along with published articles. Conclusions The open data format ElVisML ensures the quality, validity, and integrity of electrophysio- logical data transmission and storage as well as providing manufacturer-independent access and long-term archiving in a future-proof format. Stan- dardization of the format of such neurophysiology data would promote the development of new tech- niques and open software for the use of neurophysi- ological data in both clinic and research. Keywords Visual electrophysiology Á Open data format Á Standards Á Biomedical signals Á Data archiving Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10633-017-9618-6) con- tains supplementary material, which is available to authorized users. T. Strasser (&) Á T. Peters Á E. Zrenner Institute for Ophthalmic Research, University of Tuebingen, Elfriede-Aulhorn-Str. 7, 72076 Tu ¨bingen, Germany e-mail: torsten.strasser@uni-tuebingen.de H. Ja ¨gle Department of Ophthalmology, University Hospital Regensburg, Regensburg, Germany E. Zrenner Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tuebingen, Tu ¨bingen, Germany 123 Doc Ophthalmol DOI 10.1007/s10633-017-9618-6