This overview will not cover all research projects within the field of assisted living nor all available commercial products on the market. Furthermore – we will focus on infrastructure projects rather than for example pure sensor projects or usability studies, limiting the candidates further.

Seon-Woo et al. [17], are looking into the assisted living domain surveying the elderly in their own homes. An architecture is created with sensors for detecting movement and a gateway in the home for sending the data to a central server. They focus primarily on analysing the data. The system appears to be rather monolithic by nature, and does not seem open. This might be a good strategy to solve the particular scenario they are aiming at and have set as their objective, but what if the system is later adapted by a regional care center and the need arises for the system to talk with several back-end systems, or they need to support a range of hardware sensors from another vendor. Whether there is access to the source code and whether this is open source is not discussed, but this appears not to be the case, and thus not allowing for modifications or adaptations of the system.

Huang and Su [18] also looks into establishing an architecture for the home, but focuses on the conversion of signals in the home to a known format. The converted data is placed in a middleware where the format from e.g. a webcam or an ECG is formatted to the DICOM [19] format from NEMA [20]. Due to the limited amount of information on the middleware in relation to the use of technologies, this work is again deemed rather closed and limited on features. The use of standards (DICOM and NEMA) seems quite relevant, and using a middleware could be promising, if the middleware was itself heterogeneous with regards to programming languages and operation system platforms. This is not possible to deduct from the text, as is neither code availability nor licensing issues.

Varshney [21] writes about the infrastructure for monitoring the elderly at home. The research focuses on how sensors should communicate with the outside world, but does not specify a complete solution. This is again deemed a prototype project – exploring a single case, rather than providing a complete infrastructure for assisted living solutions.

Bambis et al. [22] discusses the possibility of monitoring the elderly in their homes and tracking their movement and providing a scalable framework for interpreting their movement data and a state model of their behaviour. This includes an API for asking whether the person is getting enough sleep, where the person currently is, number of visits to the toilet etc. The system allows for third party movement and tracking sensors, but it does not include e.g. ECG or blood pressure sensors. The system appears modularized and scalable. It does not however appear to be open for third party software systems, as it does not appear to be available for source code download. The system share many similarities with the OpenCare Project discussed in this paper, but appear as being rather monolithic and closed.

Kirovski et al. [23] from Microsoft Research introduces the Health-OS system. It is a system, apparently dedicated for the Microsoft Windows and Windows CE platforms (even though it is claimed it will run on any suitable real time OS based device), which integrates different commercial sensor types, collects and stores the data on standard Windows and Windows CE devices. The system appears somewhat open, including an SDK for accessing the data and functionality. However the source code does not appear to be available, again keeping the system closed for most extensions or modifications.
Schwiebert et al. [24] discusses some issues regarding biometric sensors where they point out a number of important points including problems with power supply, interruption of the elderly etc. The project is deemed more relevant for providing requirements for sensor manufacturers than it is relevant to infrastructure discussions.

Rodrig and LaMarca [25], presents a P2P architecture for collecting and distributing data from sensors. In our opinion, the complexity of an infrastructure tends to increase when using a P2P architecture, and Rodrig and LaMarca does not convince us otherwise with their system. This does not mean that it might not have its validity in some scenarios, just that a pervasive healthcare infrastructure not seems to gain anything from being P2P based.

Bardram et al. [26] discusses the transition from ordinary visits at a physician to the use of telemedicine, where the patients themselves performs the measurements and collects the data. The paper does not focus on infrastructure or architecture, but on the usage of systems suitable for home use.

Telcomed [27] is a commercial company based in Ireland, producing a range of telemedicine and pervasive healthcare products. Including sensors for monitoring heart rate, 1 lead ECG, body temperature, weight, blood pressure, blood sugar and more. They provide a complete infrastructure, from the patients home to the web-based Telcomed monitoring center. They use proprietary communication protocols, and the solution appears not to be open for third party solutions.

Figure: Overview of the Telcomed Telemedicine surveillance system and Medical Monitoring Center

Corscience [28] is likewise a commercial company, based in Germany. They also provide a complete vertical monolithic solution including sensors for ECG, blood pressure (both 1-lead and 3, 6 or 12-lead), a weigth sensor as well as an Asthma sensor device. The Corscience system can send data from either a stationary gateway, or a small mobile gateway, to a central database, and provides web-access to these data, including alert functionality and more. The Corscience system is closed like Telcomed, but they do however use Bluetooth for most sensor devices, and they do share their communication protocol with partner companies, signing an NDA. The OpenCare Project is supporting several Corscience sensors devices at present, incl. ECG, blood pressure and weight. Corscience is not open source, and not much more open than is the Telcomed solution. Again, choosing Corscience requires a full solution, and it may not work with e.g. Telcomd products.

Figure: Overview of the Corscience Deployment. Sensors communicate with relay stations to a central server, and then on to EPR's and other systems.

Yet another private company is Tunstall. Tunstall [29] has a wide range of sensor products, incl. pressure mats and movement sensors, as well as blood pressure, ECG, temperature and more. Tunstall utilizes an interactive basestation at the users home, sending the data directly to the relevant clinic. Again, the sensors are Bluetooth based, and by signing an NDA, it is possible to partner with them. Again, we see a semi open solution, which is however not open source.
Figure: Tunstall Telehealth Monitor (similar to the OpenCare Basestation) - here working with a bluetooth based blood pressure device

Intel has recently released the Intel Health Guide PHS6000 [30], which is an interactive mobile computer with a touch screen, camera and more. According to Intel, a whole range of sensor types has been certified for use with it, which sensors exactly has however not been revealed yet. The solution appears somewhat monolithic in nature, but might be open for third party sensors, as long as Intel will certify them. There is no mention of whether the system is open for external systems, including Electronic Patient Record systems, clinical systems and others. Also, there is no mention of whether the source code is available for modifications, or whether the hardware platform might be changed to something else than an Intel based machine.

Figure: the Intel Healthguide is a touch screen based computer for easy access to data

The Continua Alliance [31] is a non-profit, open industry alliance of healthcare and technology companies that has realized that “broad interoperability has yet to be achieved” [32] within the field of pervasive healthcare. They conclude that “Much of the technology that can improve healthcare already exists in some form. For example, medical devices that monitor health and fitness – blood pressure cuffs, glucose meters, medication trackers, weight scales and pedometers – are on the market; however, these pieces cannot be integrated into full personal telehealth systems that can send data from multiple vendors’ medical devices to a health care provider or fitness coach. No standards exist that fully define interoperability among these devices, thus the market is unable to invest in interoperable solutions.” [33].

The Continua Alliance has the goal of achieving interoperability between different healthcare related technologies and solutions. The Continua Alliance plan on using the ISO/IEEE 11073 family of Medical Device Connectivity standards and Bluetooth and the USB Personal Healthcare Device Class Specification as the glue to tie healthcare sensors and computing hardware together with Remote Patient Monitoring and Electronic Health Record systems [34]. The Continua Alliance is dedicated to provide developer resources (including access to some free reference source code) as well as guidelines and a certification process. The Continua Alliance is as such in many respects closely related to the mission of the OpenCare Project. However, they are more concerned with device interoperability than providing a complete and freely available end-to-end infrastructure.


  • [1] US Census Bureau, International Database. Accessed via Internet: http://www.census.gov/ipc/www/idb/, November 2008.
  • [2] T. Ezzati-Rice, D. Kashihara and S. Machlin, “Health care expenses in the United States, 2000”, Agency for Helatchare Research and Quality, Report 04.0022, 2004.
  • [3] J.E. Bardram, A. Mihailidis, D. Wan, “Pervasive Computing in Healthcare”, CRC Press, p.6, 2006.
  • [4] “Scaling Mount Proteome to bring down chronic disease”. The Pfizer Journal®, Global Edition Volume 1I, Number 2, 2001, 4-9.R.
  • [5] Centers for Disease Control and Prevention, National Center for Health Statistics, Health United States, “Limittation of acitivity caused by selected chronic health conditions among working-age adults, by age United States, 2004-2005.”, 2007, Figure 16. Data from the National Health Interview Survey. Accessed via Internet: http://www.cdc.gov/nchs/data/hus/hus07.pdf, November 2008.
  • [6] Centers for Disease Control and Prevention, National Center for Health Statistics, Health United States, “Limittation of acitivity caused by selected chronic health conditions among older adults, by age: United States, 2004-2005.”, 2007. Data from the National Health Interview Survey. Accessed via Internet: http://www.cdc.gov/nchs/data/hus/-hus07.pdf, November 2008.
  • [7] J.E. Bardram, A. Mihailidis, D. Wan, “Pervasive Computing in Healthcare”, CRC Press, 2006.
  • [8] S. Candrili, J. Mauskopf, “How much does a hospital day cost?” Presented at: 11th Annual International Meeting of the International Society for Pharmacoeconomics and Outcomes Research May 20-24 2006. Philadelphia. PA
  • [9] L.M Tolstrup, A. Bonne, Dansk Regioner, Note on the Estimated Average Value of 1 Day of Hospitalization in a Danish Public Sector Hospital, data drawn from http://www.sst.dk/-Planlaegning_og_behandling/DRG.aspx , November 2008.
  • [10] R. Bennefield, R. Bonnette, “Structural and occupancy characteristics of housing: 2000”, United States Census Bureau, Report No. C2KBR-32, 2003
  • [11] J. Keye, T. Zitzelberger, “Overview of healthcare, disease, and disability”, in “Pervasive Computing in Healthcare”, CRC Press, p. 3-20, 2006.
  • [12] R. Thractenberg, C. Singer, J. Kaye, “Symptoms of sleep disturbance in persons with Alzheimer’s disease and normal elderly”, Journal of Sleep Research 14, 177-185, 2005
  • [13] M. Weiser, “The computer for the 21st century”. In Scientific American, September, 1991.
  • [14] M. Weiser, “Some computer science issues in ubiquitous computing”. In Communications of the ACM, July 36, vol. 7, 1993.
  • [15] D. A. Norman, “The invisible computer: why good products can fail, the personal computer is so complex, and information appliances are the solution”. The MIT Press, Cambridge, Massachusetts, USA, 1998.
  • [16] H. Kautz, L. Arnstein, G. Borriello, O. Etzioni., D. Fox. “An overview of the assisted cognition project.”, AAAI-2002 Workshop on Automation as Caregiver: The Role of IntelligentTechnology in Elder Care, Edmonton, Alberta, 2002.
  • [17] Seon-Woo Lee, Yong-Joong Kim, Gi-Sup Lee, Byung-Ok Cho, Nam-Ha Lee, “A remote behavioral monitoring system for elders living alone”, Control, Automation and Systems, 2007. ICCAS '07. International Conference on, pages 2725_2730, Oct. 2007.
  • [18] C.Y. Huang and J.L. Su, “A middleware of dicom and web service for home-based elder healthcare information system”. Information Technology Applications in Biomedicine, 2007. ITAB 2007. 6th International Special Topic Conference on, p. 182-185, Nov. 2007.
  • [19] DICOM. Accessed via Internet http://medical.nema.org/ , Nov. 2008
  • [20] NEMA. Accessed via Internet http://www.medicalimaging.org/. November 2008
  • [21] U. Varshney, “Pervasive healthcare and wireless health monitoring”, Mobile Networking Applications, 12(2-3)113-127, 2007
  • [22] A. Bamis, D. Lymberopoulos, T. Teixeira, A. Savvides, “Towards precision monitoring of elders for providing assistive services”. In PETRA '08: Proceedings of the 1st international conference on Pervasive Technologies Related to Assistive Environments, pages 1-8, New York, NY, USA, 2008. ACM.
  • [23] D. Kirovski, N. Oliver, M. Sinclair, D. Tan. “Health-os: a position paper”. In HealthNet '07: Proceedings of the 1st ACM SIGMOBILE international workshop on Systems and networking support for healthcare and assisted living environments, pages 76-78, New York, NY, USA, 2007. ACM.
  • [24] L. Schwiebert, S.K.S. Gupta, and J. Weinmann, “Research challenges in wireless networks of biomedical sensors”. In MobiCom '01: Proceedings of the 7th annual international conference on Mobile computing and networking, pages 151-165, New York, NY, USA, 2001. ACM.
  • [25] M. Rodrig, A. LaMarca. “Oasis: an architecture for simplified data management and disconnected operation”. Personal Ubiquitous Computing, 9(2):108-121, 2005.
  • [26] J. E. Bardram, C. Bossen, A. Thomsen, “Designing for transformations in collaboration: a study of the deployment of homecare technology.” In GROUP '05: Proceedings of the 2005 international ACM SIGGROUP conference on Supporting group work, pages 294-303, New York, NY, USA, 2005. ACM.
  • [27] Telcomed, “About us”, Accessed via Internet: http://www-.telcomed.ie/about_us.html, November 2008
  • [28] Corscience, “Telemedicine”, Accessed via Internet: http://www.corscience.de/en/medical-engineering/products-systems/telemedicine.html , November 2008
  • [29] Tunstall, “Telehealth Monitors”, Accessed via Internet: http://www.tunstallhealthcare.com/Default.aspx?ID=2137, November 2008
  • [30] Intel, “Intel Health Guide Overview“, Accessed via Internet: http://www.intel.com/healthcare/ps/healthguide/index.htm, November 2008
  • [31] Continua Alliance, “Home Page”, Accessed via Internet: http://www.continuaalliance.org, November 2008.
  • [32] Continua Alliance, “Overview”, Accessed via Internet: http://www.continuaalliance.org/about/, November 2008.
  • [33] Continua Alliance, “Delivering on the promise of modern medicine: the need for interopable health & medical devices”, Accessed via Internet: http://www.continuaalliance.org/news_events/news/back-grounder, November 2008.
  • [34] Continua Alliance, “Continua Overview Presentation”, Accessed via Internet: http://www.continuaalliance.org/about/Continua-_Overview_Presentation_v10.1.pdf, November 2008.
  • [35] Linux Information Project Definition. “Vendor lock-in definition”, Accessed via Internet: http://www.linfo.org/vendor_lockin.html, September, 2007.
  • [36] S. Wagner, "Towards an open and easily extendible home care system infrastructure”, Proceedings of the 2nd International Conference on Pervasive Computing Technologies for Healthcare, Tampere, Finland 2008
  • [37] S. Wagner, “Zero-configuration of pervasive healthcare sensor networks” Proceedings of the The Third International Conference on Pervasive Computing and Applications (ICPCA2008), Alexandria, Egypt, 2008.
  • [38] R.A. Soerensen, J.M. Nygaard, “Distributed zero configuration base station”, Proceedings of the 2nd International Conference on Pervasive Computing Technologies for Healthcare, Tampere, Finland (2008).