Sleep and Sensory Analysis Group - Sensing everything between heaven and earth
Sleep and Sensory Signal Analysis Group

Examples of our studies

Sleep analysis
Epilepsy analysis
Measurement chair
Sensing the human
Tablet interface
Other user interface studies
Engine signal processing
Health informatics standardisation
Secret company projects
Ancient web history

Doctoral theses

Health informatics standardisation

Logos of SDOs
Logos of standardisers in health informatics.
  Aiming at medical device interoperability

There exists a dream that one day it is possible to exchange a device in a medical device system with another medical device for the same purpose but from a different manufacturer and still the data would flow as if nothing had happened. This is what is ment with medical device interoperability. In order to realize this dream experts are working in standard development organisations (SDOs) such as European Committee for Standardisation (CEN), International Organization for Standardization (ISO), IEEE (originally an acronym for the Institute of Electrical and Electronics Engineers), DICOM (Digital Imaging and Communication in Medicine) and Health Level Seven (HL7).

Nowadays when the devices communicate in digital form, this does not simply mean that the connectors fit and that voltage levels and timings in the wires are the same. The compatibility of data packets, representation formats, coding schemes and data models are required, too. This has kept the experts busy from the early 1990'ies and the work still goes on. Recently most rapid development has been seen in the standardisation of communication of personal health devices within IEEE 11073.

The contributions of the members of Sleep and Sensory Signal Analysis Group have been mainly in the development of a standard file format to store and exchange physiological signal recordings. The first result was the publication of the European Data Format (EDF) specification in 1992. EDF has since been adopted by a number of research groups in the field and also by many polysomnographic and EEG device manufacturers as one of the export formats they support. After EDF, the work towards the European technical specification ENV 14271 File Exchange Format for Vital Signs was participated and also for the basic standard of medical device interoperability, EN 13734 Vital Signs Information Representation. This work continues nowadays within ISO/TC215/WG7 and IEEE 11073 committees. Yet another piece of work contributed by the group was the technical report on Interoperability of Healthcare Multimedia Report Systems by CEN/TC251/PT34. Alpo Värri has represented Finland in CEN/TC251/WGIV and ISO/TC215/WG7 and reported about these activities to the Finnish mirror panel.
CEN e-health interoperability
ISO TC215 Health Informatics
European data format (EDF)
IEEE Standards Association, (search for "health informatics")
E-mail to Alpo.Varri (at)
Designed by Alpo Värri 28.1.2013
Department of Signal Processing Tampere University of Technology
P.O. Box 553, FI-33101 Tampere, Finland, Tel. +358-40-8490780