Klaus-Hendrik Wolf

On Health-enabling and Ambient-assistive Technologies

Objectives: To provide an introductory overview on selected areas of health-enabling and ambient-assistive technologies and to suggest relevant fields for future research. Methods: Summarizing the state of the art for 1) ambient environments and 2) health-related sensor technologies, 3) presenting relevant medical conditions and their relation to health-enabling technologies, and 4) illustrating the application of those technologies for lifestyle management with examples for activity monitoring and prevention of overweight. The suggestions for future research are based on own research projects in this field. Results: Health-enabling and ambient-assistive technologies are regarded to have the potential to significantly improve quality of life and efficiency of health care in aging societies. Research on health-enabling and ambient-assistive technologies is highly multidisciplinary. Conclusions: It still has, to a large extent, to be exploratory. An increasing amount of outcomes research through well-designed evaluation studies that explore technical solutions in a social context and in relation to individual needs will be crucial.

Health-enabling technologies for the elderly - An overview of services based on a literature review

BACKGROUND Services for the elderly based on health-enabling technologies promise to contribute significantly to the efficiency and effectiveness of future health care. Due to this promise, over the last years the scientific community has designed a complex variety of these valuable innovations. A systematic overview of the developed services would help to better understand their opportunities and limitations. OBJECTIVE To obtain a systematic overview of services for the elderly based on health-enabling technologies and to identify archetypical service categories. METHODS We conducted a literature review using PubMed and retrieved 1447 publications. We stepwise reduced this list to 27 key publications that describe typical service archetypes. RESULTS We present six archetypical service categories, namely handling adverse conditions, assessing state of health, consultation and education, motivation and feedback, service ordering and social inclusion and describe their implementation in current research projects.

Health-enabling technologies for pervasive health care: on services and ICT architecture paradigms

Background. Progress in information and communication technologies (ICT) is providing new opportunities for pervasive health care services in aging societies. Objectives. To identify starting points of health-enabling technologies for pervasive health care. To describe typical services of and contemporary ICT architecture paradigms for pervasive health care. Methods. Summarizing outcomes of literature analyses and results from own research projects in this field. Results. Basic functions for pervasive health care with respect to home care comprise emergency detection and alarm, disease management, as well as health status feedback and advice. These functions are complemented by optional (non-health care) functions. Four major paradigms for contemporary ICT architectures are person-centered ICT architectures, home-centered ICT architectures, telehealth service-centered ICT architectures and health care institution-centered ICT architectures. Conclusions. Health-enabling technologies may lead to both new ways of living and new ways of health care. Both ways are interwoven. This has to be considered for appropriate ICT architectures of sensor-enhanced health information systems. IMIA, the International Medical Informatics Association, may be an appropriate forum for interdisciplinary research exchange on health-enabling technologies for pervasive health care.

Assessing elderly persons' fall risk using spectral analysis on accelerometric data - a clinical evaluation study

Falls are among the leading causes for morbidity, mortality and lasting functional disability in the elderly population. Several studies have shown the applicability of accelerometry to detect persons with a high fall risk. Most of these studies have been conducted under laboratory settings and without clear definition of ‘fall risk’ reference measures. The aim of our work is to provide a simple unsupervised method to assess the fall risk of elderly persons as measured by reference clinical fall risk assessment scores. Our method uses parameters computed by spectral analysis on triaxial accelerometer data recorded in a clinical setting, and is evaluated using simple logistic regression classifier models with reference to three clinical reference scores. The overall prediction accuracy of the models ranges from 65.5–89.1%, with sensitivity and specificity between 78.5–99% and 15.4–60.4%, respectively. Our results show that our simple method can be used to detect persons with a high fall risk with a fair to good predictive accuracy when tested against common clinical reference scores. Our parameters are independent of specific test procedures and therefore are suited for use in an unsupervised setting. Our future research will include the evaluation of our method in a large prospective study.

Towards New Scopes: Sensor-enhanced Regional Health Information Systems - Part 1: Architectural Challenges

OBJECTIVES To analyze utilization of sensor technology in telemonitoring and home care and to discuss concepts and challenges of sensor-enhanced regional health information systems (rHIS). METHODS The study is based upon experience in sensor-based telemedicine and rHIS projects, and on an analysis of HIS-related journal publications from 2003 to 2005 conducted in the context of publishing the IMIA Yearbook of Medical Informatics. RESULTS Health-related parameters that are subject to sensor-based measurement in home care and telemonitoring are identified. Publications related to telemonitoring, home care and smart houses are analyzed concerning scope and utilization of sensor technology. Current approaches for integrating sensor technology in rHIS based on a corresponding eHealth infrastructure are identified. Based on a coarse architecture of home care and telemonitoring systems ten challenges for sensor-enhanced rHIS are identified and discussed: integration of home and health telematic platforms towards a sensor-enhanced telematic platform, transmission rate guarantees, ad hoc connectivity, cascading data analysis, remote configuration, message and alert logistic, sophisticated user interfaces, unobtrusiveness, data safety and security, and electronic health record integration. CONCLUSIONS Utilization of sensor technology in health care is an active field of research. Currently few research projects and standardization initiatives focus on general architectural considerations towards suitable telematic platforms for establishing sensor-enhanced rHIS. Further research finalized by corresponding standardization is needed. Part 2 of this paper will present experiences with a research prototype for a sensor-enhanced rHIS telematic platform.

The Lower Saxony research network design of environments for ageing: towards interdisciplinary research on information and communication technologies in ageing societies

Worldwide, ageing societies are bringing challenges for independent living and healthcare. Health-enabling technologies for pervasive healthcare and sensor-enhanced health information systems offer new opportunities for care. In order to identify, implement and assess such new information and communication technologies (ICT) the ‘Lower Saxony Research Network Design of Environments for Ageing’ (GAL) has been launched in 2008 as interdisciplinary research project. In this publication, we inform about the goals and structure of GAL, including first outcomes, as well as to discuss the potentials and possible barriers of such highly interdisciplinary research projects in the field of health-enabling technologies for pervasive healthcare. Although GALs high interdisciplinarity at the beginning slowed down the speed of research progress, we can now work on problems, which can hardly be solved by one or few disciplines alone. Interdisciplinary research projects on ICT in ageing societies are needed and recommended.

Monitoring systems for the support of home care.

In this article, the design of a system for the ambient, unobtrusive and automatic monitoring of Activities of Daily Living (ADL) is described. In the context of the growing imbalance between (potentially young) caregivers and (most often older) people receiving care, technical monitoring systems may help to organise care more efficiently and to identify degrading abilities very early to trigger preventive measures. To improve the acceptance of the system described in this article, the selection process of the sensors to be integrated into the flat or to be worn by the older people has been steered by the results of focus group interviews with older people, their relatives and professional caregivers. The interviews revealed that these people would in general accept such systems, but security, mobility and communication aspects have to be clearly and appropriately addressed. In an experimental study the recognition rate of the activity ‘preparation and intake of food or beverages’ has been measured with two age groups (6 subjects, age between 25 and 40/mean 30 years and 5 subjects, age between 72 and 84/mean 75.3 years). The food preparation was detected with a sensitivity of 74.7% and a specificity of 84.2% using a vision sensor.

Wearable sensors in healthcare and sensor-enhanced health information systems: all our tomorrows?

Wearable sensor systems which allow for remote or self-monitoring of health-related parameters are regarded as one means to alleviate the consequences of demographic change. This paper aims to summarize current research in wearable sensors as well as in sensor-enhanced health information systems. Wearable sensor technologies are already advanced in terms of their technical capabilities and are frequently used for cardio-vascular monitoring. Epidemiologic predictions suggest that neuropsychiatric diseases will have a growing impact on our health systems and thus should be addressed more intensively. Two current project examples demonstrate the benefit of wearable sensor technologies: long-term, objective measurement under daily-life, unsupervised conditions. Finally, up-to-date approaches for the implementation of sensor-enhanced health information systems are outlined. Wearable sensors are an integral part of future pervasive, ubiquitous and person-centered health care delivery. Future challenges include their integration into sensor-enhanced health information systems and sound evaluation studies involving measures of workload reduction and costs.

Information and communication technologies for promoting and sustaining quality of life, health and self-sufficiency in ageing societies – outcomes of the Lower Saxony Research Network Design of Environments for Ageing (GAL)

Many societies across the world are confronted with demographic changes, usually related to increased life expectancy and, often, relatively low birth rates. Information and communication technologies (ICT) may contribute to adequately support senior citizens in aging societies with respect to quality of life and quality and efficiency of health care processes. For investigating and for providing answers on whether new information and communication technologies can contribute to keeping, or even improving quality of life, health and self-sufficiency in ageing societies through new ways of living and new forms of care, the Lower Saxony Research Network Design of Environments for Ageing (GAL) had been established as a five years research project, running from 2008 to 2013. Ambient-assisted living (AAL) technologies in personal and home environments were especially important. In this article we report on the GAL project, and present some of its major outcomes after five years of research. We report on major challenges and lessons learned in running and organizing such a large, inter- and multidisciplinary project and discuss GAL in the context of related research projects. With respect to research outcomes, we have, for example, learned new knowledge about multimodal and speech-based human–machine-interaction mechanisms for persons with functional restrictions, and identified new methods and developed new algorithms for identifying activities of daily life and detecting acute events, particularly falls. A total of 79 apartments of senior citizens had been equipped with specific “GAL technology”, providing new insights into the use of sensor data for smart homes. Major challenges we had to face were to deal constructively with GAL’s highly inter- and multidisciplinary aspects, with respect to research into GAL’s application scenarios, shifting from theory and lab experimentation to field tests, and the complexity of organizing and, in our view, successfully managing such a large project. Overall it can be stated that, from our point of view, the GAL research network has been run successfully and has achieved its major research objectives. Since we now know much more on how and where to use AAL technologies for new environments of living and new forms of care, a future focus for research can now be outlined for systematically planned studies, scientifically exploring the benefits of AAL technologies for senior citizens, in particular with respect to quality of life and the quality and efficiency of health care.

Performance comparison of accelerometer calibration algorithms based on 3D-ellipsoid fitting methods

Calibration of accelerometers can be reduced to 3D-ellipsoid fitting problems. Changing extrinsic factors like temperature, pressure or humidity, as well as intrinsic factors like the battery status, demand to calibrate the measurements permanently. Thus, there is a need for fast calibration algorithms, e.g. for online analyses. The primary aim of this paper is to propose a non-iterative calibration algorithm for accelerometers with the focus on minimal execution time and low memory consumption. The secondary aim is to benchmark existing calibration algorithms based on 3D-ellipsoid fitting methods. We compared the algorithms regarding the calibration quality and the execution time as well as the number of quasi-static measurements needed for a stable calibration. As evaluation criterion for the calibration, both the norm of calibrated real-life measurements during inactivity and simulation data was used. The algorithms showed a high calibration quality, but the execution time differed significantly. The calibration method proposed in this paper showed the shortest execution time and a very good performance regarding the number of measurements needed to produce stable results. Furthermore, this algorithm was successfully implemented on a sensor node and calibrates the measured data on-the-fly while continuously storing the measured data to a microSD-card.