Ilkka Korhonen | Tampere University (original) (raw)
Papers by Ilkka Korhonen
Translational Behavioral Medicine, 2015
Health risks and chronic conditions today are largely the result of suboptimal behaviour and life... more Health risks and chronic conditions today are largely the result of suboptimal behaviour and lifestyles, such as physical inactivity, excess energy intake, and stress. These risk factors cluster and interact in individuals, and thus need to be managed together. Behavioural change towards healthy lifestyles is the key to managing health and chronic illnesses. However, changing behaviours permanently is a difficult and long-term process, requiring practice and long-term support, which cannot be provided through the current healthcare system. Personal Health Systems (PHS), including Web, mobile, and monitoring technologies, offer cost-efficient and personalized tools for long-term health management. They can be used independently or as a part of a health promotion intervention or chronic disease management program. We have developed and evaluated a multifactor PHS approach in occupational health promotion and management of psychophysiological wellbeing. Our findings outline the success...
Translational Behavioral Medicine, 2015
Lecture Notes in Computer Science, 2003
... In: Proceedings of 2000 IEEE EMBS International Conference on Information Technology Applicat... more ... In: Proceedings of 2000 IEEE EMBS International Conference on Information Technology Applications in Biomedicine, ITAB ... T., Ltjnen, J., Cluitmans, L., Korhonen, I.: Feasibility and useracceptance of a personal weight management system based on ubiquitous computing. ...
Methods of information in medicine, 1997
This paper introduces a closed-loop model for the analysis of interactions between heart rate and... more This paper introduces a closed-loop model for the analysis of interactions between heart rate and blood pressure variability, and respiration. The respiratory influence is modeled with an anti-causal structure to control the possible phase lead of heart rate to instantaneous lung volume. The closed-loop structure between heart rate and blood pressure allows the analysis of inter-relationships between the signals. Simulations and results on experimental data show the identifiability of the model and the robustness of the noise source contribution analysis over a wide range of model orders.
Journal of telemedicine and telecare, 2010
We studied self-observations related to weight management recorded with a Wellness Diary applicat... more We studied self-observations related to weight management recorded with a Wellness Diary application on a mobile phone. The data were recorded by 27 participants in a 12-week study, which included a short weight management lecture followed by independent usage of the Wellness Diary. We studied the validity of self-observed weight, and behavioural changes and weight patterns related to weight management success. Self-observed weight data tended to underestimate pre- and poststudy measurements, but there were high correlations between the measures (r >or= 0.80). The amount of physical activity correlated significantly with weight loss (r = 0.44) as did different measures representing healthy changes in dietary behaviours (r >or= 0.45). Weight changes and the weekly rhythms of weight indicated a strong tendency to compensate for high-risk periods among successful weight-losers compared to unsuccessful ones. These preliminary results suggest that the mobile phone diary is a valid ...
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2008
Majority of the health risks and diseases in the modern world are related to lifestyles, e.g., ov... more Majority of the health risks and diseases in the modern world are related to lifestyles, e.g., overweight, unhealthy diet, physical inactivity, sleep deprivation, and stress. Behavioral change towards healthy lifestyles is the key to the prevention and management of these risks, but early and efficient interventions are scarcely available. We present the Nuadu Concept, an ICT (Information and Communication Technologies) assisted wellness toolbox for the management of multiple, behavior-originated health risks. The concept is based on psychological models, which provide methods and motivation for behavior change. The individual is considered as the best expert of his/her own wellness. Thus, the Nuadu Concept provides a variety of personal wellness technologies and services, among which the user may freely choose the best tools for him/herself. We believe this approach has the potential to provide efficient, acceptable, available, and affordable wellness management support for a signi...
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
Sleep quality is one of the key elements of the human health status. By observing sleep patterns ... more Sleep quality is one of the key elements of the human health status. By observing sleep patterns we can gain information about personal wellbeing. Consumer electronic sleep analysis solutions are now available for use in long-term conditions. In this study we compare different measures for total sleep time and sleep quality. We analyzed visually long- term sleep data collected with actigraphy, sleep logs and ambient sensors to gain more reliable results and compared these results to each single method's output. Correlations of visually analyzed total sleep time between actigraphy total sleep time (correlation coefficient (r) = 0.662, p <0.01) and sleep log total sleep time (r = 0.787, p <0.01) were high. Also comparison between subjective and objective sleep quality was analyzed and small, but significant correlation was found (r = 0.270, p < 0.01).
Proceedings of the 3d International ICST Conference on Pervasive Computing Technologies for Healthcare, 2009
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
To develop technology -based service solutions for supporting the independent living of elderly c... more To develop technology -based service solutions for supporting the independent living of elderly citizens, we conducted a user assessment study. Six different service scenarios were created and analyzed in six focus groups by young adults, elderly, and health-care professionals (n=29). Results show that safety was viewed as the most significant aspect. The study also showed that independent of age, most individuals take interest in health related issues only when a clear threat is posed, even though health in general is considered an important issue in life.
IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), 2014
ABSTRACT Health interventions aim to influence behavior by creating healthy habits that substitut... more ABSTRACT Health interventions aim to influence behavior by creating healthy habits that substitute existing unhealthy ones. Habits are often deeply ingrained but also easily disrupted in new situations. This makes changing habits a life-long learning and adaptation process rather than a one-time task of limited duration. Therefore, applying modern understanding of learning could be fruitful in designing effective and sustainable health interventions. This paper presents the initial design framework for interventions based on learning theories, and also introduces a mobile habit change application. The application guides the user in habit formation through small daily changes, supported by a user-selectable cartoonish avatar with varied styles of dialogue.
International Workshop on Wearable and Implantable Body Sensor Networks (BSN'06), 2006
The IEEE Engineering in Medicine and Biology Society (EMBS) established a technical committee on ... more The IEEE Engineering in Medicine and Biology Society (EMBS) established a technical committee on wearable biomedical sensors and systems (WBSS) in 2004. This position paper presents the view of the technical committee on the field of wearable sensors and systems in medicine, and shortly introduces its plan of action. The purpose of the position paper is to raise awareness of
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
Lifestyle related health risks, such as overweight, work stress, and physical inactivity, have be... more Lifestyle related health risks, such as overweight, work stress, and physical inactivity, have become pervasive in most modern societies. These risk factors have a debilitating impact on the wellbeing of citizens and play a major role in the onset of many chronic diseases. As a result, working life is affected due to impaired work ability, decreased productivity, absenteeism, and disability pensions. Lifestyle changes are the key to managing these problems, but they are often difficult to accomplish and maintain. We present a concept for ICT (Information and Communication Technology) assisted health promotion in the occupational healthcare. ICT tools are provided for employees participating in a face-to-face intervention, which is designed to address several health risks. We believe that through ICT, we can provide the employees with more personalized health management support more efficiently than before. The ICT system will be implemented by integrating different technologies into an interoperable system.
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006
We study the possibility of applying an emerging RFID-based communication technology, NFC (Near F... more We study the possibility of applying an emerging RFID-based communication technology, NFC (Near Field Communication), to health monitoring. We suggest that NFC is, compared to other competing technologies, a high-potential technology for short-range connectivity between health monitoring devices and mobile terminals. We propose practices to apply NFC to some health monitoring applications and study the benefits that are attainable with NFC. We compare NFC to other short-range communication technologies such as Bluetooth and IrDA, and study the possibility of improving the usability of health monitoring devices with NFC. We also introduce a research platform for technical evaluation, applicability study and application demonstrations of NFC.
2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2009
Poor lifestyles - overweight, unhealthy diet, physical inactivity, sleep deprivation, and stress ... more Poor lifestyles - overweight, unhealthy diet, physical inactivity, sleep deprivation, and stress - are significant risk factors to chronic illnesses, which cause majority of the health care costs. Hence, behavioral change towards healthy lifestyles is one of the keys to health care cost containment. Personal health systems (PHS) offer tools to support behavioral change. As health risks, personal needs and preferences vary from an individual to another, personalization of the PHS is needed. In Nuadu project we have developed a PHS integrating several different personal health technologies. This system was studied in a large (N=354) randomized controlled trial where employees with several health risks participated in a health promotion program. The study will finish in June 2009. User feedback and technology usage logs reveal that especially simple mobile technologies were actively used during the program. However, usage models varied between individuals and time, and there was a significant number of both active users and non-users. The results emphasize that "one size" does not fit all, and instead of individual "killer applications", PHS with different personalizable and interoperable options should be developed. In addition, screening and profiling methods should be developed to identify those users who would best accept and benefit from technology-supported health promotion. Successful technologies combine high usability and conceptual simplicity to clear and perceivable added value for the end users.
The Proceedings of the Second ICST International Conference on Pervasive Computing Technologies for Healthcare, 2008
Personal and Ubiquitous Computing, 2006
Medical & Biological Engineering & Computing, 1996
Multivariate autoregressive modelling provides a method to analyse the dynamic interactions betwe... more Multivariate autoregressive modelling provides a method to analyse the dynamic interactions between heart rate (HR), blood pressure (BP) and respiration (RESP) by means of noise source contributions (NSCs). The conventional approach presumes the modelled noise sources are mutually independent. This presumption is, in general, not satisfied and causes an error in the results. In the present study, the effect of this error is analysed. A method is presented to remove the error by making the noise sources independent. The method is based on the inclusion of immediate transfer paths in the model. To quantify the strength of the interactions, a measure called NSC ratio (NSCR); is calculated; this states the amount of variability of the signal arising from other signals. The method is demonstrated by studying the inter-relationships between HR, BP and RESP in a healthy male subject in supine and standing positions. It is found that the error is marked and that the presented method provides corrected estimates for spectral decomposition and NSC analysis. The results show it is necessary to include the immediate transfer mechanisms in the model, while analysing the cardiopulmonary dynamics by means of HR and BP variability.
Medical & Biological Engineering & Computing, 1995
We studied the pulsatile component of cerebral circulation with transcephalic electrical impedanc... more We studied the pulsatile component of cerebral circulation with transcephalic electrical impedance (delta Z) in six preterm newborns, three of whom had severe cerebral bleeding, peri-intraventricular haemorrhage (PIVH). The transcephalic electrical impedance delta Z signal, ECG, arterial blood pressure, (aBP) and respirogram were recorded on analogue magnetic tape for 30 min. Artefact-free stationary segments (lasting for 2 min) of the four signals were digitised. A digital multivariate autoregressive (MAR) model was used to study frequency-specific variability in the signals and to quantify interrelations between the variabilities of delta Z, HR, aBP and respiratory signals. MAR modelling describes a system where all the signals simultaneously explain each other. The inherent variability of delta Z was lower and the influences of respiration and aBP on delta Z significantly greater in infants with severe PIVH than in controls. These changes were observed at high frequencies corresponding to respiration and heart rate. This may be interpreted as a marker of pressure passivism in the cerebral circulation following PIVH. We conclude that in preterm babies the application of MAR modelling, together with transcephalic impedance, may be a new, helpful and quantitative method for the study of simultaneous interrelations between variables of cerebral and systemic circulations and respiration.
Journal of Sleep Research, 2005
Translational Behavioral Medicine, 2015
Health risks and chronic conditions today are largely the result of suboptimal behaviour and life... more Health risks and chronic conditions today are largely the result of suboptimal behaviour and lifestyles, such as physical inactivity, excess energy intake, and stress. These risk factors cluster and interact in individuals, and thus need to be managed together. Behavioural change towards healthy lifestyles is the key to managing health and chronic illnesses. However, changing behaviours permanently is a difficult and long-term process, requiring practice and long-term support, which cannot be provided through the current healthcare system. Personal Health Systems (PHS), including Web, mobile, and monitoring technologies, offer cost-efficient and personalized tools for long-term health management. They can be used independently or as a part of a health promotion intervention or chronic disease management program. We have developed and evaluated a multifactor PHS approach in occupational health promotion and management of psychophysiological wellbeing. Our findings outline the success...
Translational Behavioral Medicine, 2015
Lecture Notes in Computer Science, 2003
... In: Proceedings of 2000 IEEE EMBS International Conference on Information Technology Applicat... more ... In: Proceedings of 2000 IEEE EMBS International Conference on Information Technology Applications in Biomedicine, ITAB ... T., Ltjnen, J., Cluitmans, L., Korhonen, I.: Feasibility and useracceptance of a personal weight management system based on ubiquitous computing. ...
Methods of information in medicine, 1997
This paper introduces a closed-loop model for the analysis of interactions between heart rate and... more This paper introduces a closed-loop model for the analysis of interactions between heart rate and blood pressure variability, and respiration. The respiratory influence is modeled with an anti-causal structure to control the possible phase lead of heart rate to instantaneous lung volume. The closed-loop structure between heart rate and blood pressure allows the analysis of inter-relationships between the signals. Simulations and results on experimental data show the identifiability of the model and the robustness of the noise source contribution analysis over a wide range of model orders.
Journal of telemedicine and telecare, 2010
We studied self-observations related to weight management recorded with a Wellness Diary applicat... more We studied self-observations related to weight management recorded with a Wellness Diary application on a mobile phone. The data were recorded by 27 participants in a 12-week study, which included a short weight management lecture followed by independent usage of the Wellness Diary. We studied the validity of self-observed weight, and behavioural changes and weight patterns related to weight management success. Self-observed weight data tended to underestimate pre- and poststudy measurements, but there were high correlations between the measures (r >or= 0.80). The amount of physical activity correlated significantly with weight loss (r = 0.44) as did different measures representing healthy changes in dietary behaviours (r >or= 0.45). Weight changes and the weekly rhythms of weight indicated a strong tendency to compensate for high-risk periods among successful weight-losers compared to unsuccessful ones. These preliminary results suggest that the mobile phone diary is a valid ...
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2008
Majority of the health risks and diseases in the modern world are related to lifestyles, e.g., ov... more Majority of the health risks and diseases in the modern world are related to lifestyles, e.g., overweight, unhealthy diet, physical inactivity, sleep deprivation, and stress. Behavioral change towards healthy lifestyles is the key to the prevention and management of these risks, but early and efficient interventions are scarcely available. We present the Nuadu Concept, an ICT (Information and Communication Technologies) assisted wellness toolbox for the management of multiple, behavior-originated health risks. The concept is based on psychological models, which provide methods and motivation for behavior change. The individual is considered as the best expert of his/her own wellness. Thus, the Nuadu Concept provides a variety of personal wellness technologies and services, among which the user may freely choose the best tools for him/herself. We believe this approach has the potential to provide efficient, acceptable, available, and affordable wellness management support for a signi...
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
Sleep quality is one of the key elements of the human health status. By observing sleep patterns ... more Sleep quality is one of the key elements of the human health status. By observing sleep patterns we can gain information about personal wellbeing. Consumer electronic sleep analysis solutions are now available for use in long-term conditions. In this study we compare different measures for total sleep time and sleep quality. We analyzed visually long- term sleep data collected with actigraphy, sleep logs and ambient sensors to gain more reliable results and compared these results to each single method's output. Correlations of visually analyzed total sleep time between actigraphy total sleep time (correlation coefficient (r) = 0.662, p <0.01) and sleep log total sleep time (r = 0.787, p <0.01) were high. Also comparison between subjective and objective sleep quality was analyzed and small, but significant correlation was found (r = 0.270, p < 0.01).
Proceedings of the 3d International ICST Conference on Pervasive Computing Technologies for Healthcare, 2009
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
To develop technology -based service solutions for supporting the independent living of elderly c... more To develop technology -based service solutions for supporting the independent living of elderly citizens, we conducted a user assessment study. Six different service scenarios were created and analyzed in six focus groups by young adults, elderly, and health-care professionals (n=29). Results show that safety was viewed as the most significant aspect. The study also showed that independent of age, most individuals take interest in health related issues only when a clear threat is posed, even though health in general is considered an important issue in life.
IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), 2014
ABSTRACT Health interventions aim to influence behavior by creating healthy habits that substitut... more ABSTRACT Health interventions aim to influence behavior by creating healthy habits that substitute existing unhealthy ones. Habits are often deeply ingrained but also easily disrupted in new situations. This makes changing habits a life-long learning and adaptation process rather than a one-time task of limited duration. Therefore, applying modern understanding of learning could be fruitful in designing effective and sustainable health interventions. This paper presents the initial design framework for interventions based on learning theories, and also introduces a mobile habit change application. The application guides the user in habit formation through small daily changes, supported by a user-selectable cartoonish avatar with varied styles of dialogue.
International Workshop on Wearable and Implantable Body Sensor Networks (BSN'06), 2006
The IEEE Engineering in Medicine and Biology Society (EMBS) established a technical committee on ... more The IEEE Engineering in Medicine and Biology Society (EMBS) established a technical committee on wearable biomedical sensors and systems (WBSS) in 2004. This position paper presents the view of the technical committee on the field of wearable sensors and systems in medicine, and shortly introduces its plan of action. The purpose of the position paper is to raise awareness of
2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2007
Lifestyle related health risks, such as overweight, work stress, and physical inactivity, have be... more Lifestyle related health risks, such as overweight, work stress, and physical inactivity, have become pervasive in most modern societies. These risk factors have a debilitating impact on the wellbeing of citizens and play a major role in the onset of many chronic diseases. As a result, working life is affected due to impaired work ability, decreased productivity, absenteeism, and disability pensions. Lifestyle changes are the key to managing these problems, but they are often difficult to accomplish and maintain. We present a concept for ICT (Information and Communication Technology) assisted health promotion in the occupational healthcare. ICT tools are provided for employees participating in a face-to-face intervention, which is designed to address several health risks. We believe that through ICT, we can provide the employees with more personalized health management support more efficiently than before. The ICT system will be implemented by integrating different technologies into an interoperable system.
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006
We study the possibility of applying an emerging RFID-based communication technology, NFC (Near F... more We study the possibility of applying an emerging RFID-based communication technology, NFC (Near Field Communication), to health monitoring. We suggest that NFC is, compared to other competing technologies, a high-potential technology for short-range connectivity between health monitoring devices and mobile terminals. We propose practices to apply NFC to some health monitoring applications and study the benefits that are attainable with NFC. We compare NFC to other short-range communication technologies such as Bluetooth and IrDA, and study the possibility of improving the usability of health monitoring devices with NFC. We also introduce a research platform for technical evaluation, applicability study and application demonstrations of NFC.
2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2009
Poor lifestyles - overweight, unhealthy diet, physical inactivity, sleep deprivation, and stress ... more Poor lifestyles - overweight, unhealthy diet, physical inactivity, sleep deprivation, and stress - are significant risk factors to chronic illnesses, which cause majority of the health care costs. Hence, behavioral change towards healthy lifestyles is one of the keys to health care cost containment. Personal health systems (PHS) offer tools to support behavioral change. As health risks, personal needs and preferences vary from an individual to another, personalization of the PHS is needed. In Nuadu project we have developed a PHS integrating several different personal health technologies. This system was studied in a large (N=354) randomized controlled trial where employees with several health risks participated in a health promotion program. The study will finish in June 2009. User feedback and technology usage logs reveal that especially simple mobile technologies were actively used during the program. However, usage models varied between individuals and time, and there was a significant number of both active users and non-users. The results emphasize that "one size" does not fit all, and instead of individual "killer applications", PHS with different personalizable and interoperable options should be developed. In addition, screening and profiling methods should be developed to identify those users who would best accept and benefit from technology-supported health promotion. Successful technologies combine high usability and conceptual simplicity to clear and perceivable added value for the end users.
The Proceedings of the Second ICST International Conference on Pervasive Computing Technologies for Healthcare, 2008
Personal and Ubiquitous Computing, 2006
Medical & Biological Engineering & Computing, 1996
Multivariate autoregressive modelling provides a method to analyse the dynamic interactions betwe... more Multivariate autoregressive modelling provides a method to analyse the dynamic interactions between heart rate (HR), blood pressure (BP) and respiration (RESP) by means of noise source contributions (NSCs). The conventional approach presumes the modelled noise sources are mutually independent. This presumption is, in general, not satisfied and causes an error in the results. In the present study, the effect of this error is analysed. A method is presented to remove the error by making the noise sources independent. The method is based on the inclusion of immediate transfer paths in the model. To quantify the strength of the interactions, a measure called NSC ratio (NSCR); is calculated; this states the amount of variability of the signal arising from other signals. The method is demonstrated by studying the inter-relationships between HR, BP and RESP in a healthy male subject in supine and standing positions. It is found that the error is marked and that the presented method provides corrected estimates for spectral decomposition and NSC analysis. The results show it is necessary to include the immediate transfer mechanisms in the model, while analysing the cardiopulmonary dynamics by means of HR and BP variability.
Medical & Biological Engineering & Computing, 1995
We studied the pulsatile component of cerebral circulation with transcephalic electrical impedanc... more We studied the pulsatile component of cerebral circulation with transcephalic electrical impedance (delta Z) in six preterm newborns, three of whom had severe cerebral bleeding, peri-intraventricular haemorrhage (PIVH). The transcephalic electrical impedance delta Z signal, ECG, arterial blood pressure, (aBP) and respirogram were recorded on analogue magnetic tape for 30 min. Artefact-free stationary segments (lasting for 2 min) of the four signals were digitised. A digital multivariate autoregressive (MAR) model was used to study frequency-specific variability in the signals and to quantify interrelations between the variabilities of delta Z, HR, aBP and respiratory signals. MAR modelling describes a system where all the signals simultaneously explain each other. The inherent variability of delta Z was lower and the influences of respiration and aBP on delta Z significantly greater in infants with severe PIVH than in controls. These changes were observed at high frequencies corresponding to respiration and heart rate. This may be interpreted as a marker of pressure passivism in the cerebral circulation following PIVH. We conclude that in preterm babies the application of MAR modelling, together with transcephalic impedance, may be a new, helpful and quantitative method for the study of simultaneous interrelations between variables of cerebral and systemic circulations and respiration.
Journal of Sleep Research, 2005