43 research outputs found
The Parameter Houlihan: a solution to high-throughput identifiability indeterminacy for brutally ill-posed problems
One way to interject knowledge into clinically impactful forecasting is to
use data assimilation, a nonlinear regression that projects data onto a
mechanistic physiologic model, instead of a set of functions, such as neural
networks. Such regressions have an advantage of being useful with particularly
sparse, non-stationary clinical data. However, physiological models are often
nonlinear and can have many parameters, leading to potential problems with
parameter identifiability, or the ability to find a unique set of parameters
that minimize forecasting error. The identifiability problems can be minimized
or eliminated by reducing the number of parameters estimated, but reducing the
number of estimated parameters also reduces the flexibility of the model and
hence increases forecasting error. We propose a method, the parameter Houlihan,
that combines traditional machine learning techniques with data assimilation,
to select the right set of model parameters to minimize forecasting error while
reducing identifiability problems. The method worked well: the data
assimilation-based glucose forecasts and estimates for our cohort using the
Houlihan-selected parameter sets generally also minimize forecasting errors
compared to other parameter selection methods such as by-hand parameter
selection. Nevertheless, the forecast with the lowest forecast error does not
always accurately represent physiology, but further advancements of the
algorithm provide a path for improving physiologic fidelity as well. Our hope
is that this methodology represents a first step toward combining machine
learning with data assimilation and provides a lower-threshold entry point for
using data assimilation with clinical data by helping select the right
parameters to estimate
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Evaluating New Interactions in Healthcare: Challenges and Approaches
New technologies for supporting the provision of healthcare are increasingly pervasive. While healthcare computing previously referred to a desktop computer within the consulting room, we are now seeing an ever broader range of software, hardware and settings. This workshop is concerned with how to conduct evaluations which allow assessment of the overall impact of technology. The workshop will explore challenges and approaches for evaluating new interactions in healthcare. In this paper we outline the goals for this workshop and summarize the issues and questions it intends to explore
The Parameter Houlihan: a solution to high-throughput identifiability indeterminacy for brutally ill-posed problems
One way to interject knowledge into clinically impactful forecasting is to use data assimilation, a nonlinear regression that projects data onto a mechanistic physiologic model, instead of a set of functions, such as neural networks. Such regressions have an advantage of being useful with particularly sparse, non-stationary clinical data. However, physiological models are often nonlinear and can have many parameters, leading to potential problems with parameter identifiability, or the ability to find a unique set of parameters that minimize forecasting error. The identifiability problems can be minimized or eliminated by reducing the number of parameters estimated, but reducing the number of estimated parameters also reduces the flexibility of the model and hence increases forecasting error. We propose a method, the parameter Houlihan, that combines traditional machine learning techniques with data assimilation, to select the right set of model parameters to minimize forecasting error while reducing identifiability problems. The method worked well: the data assimilation-based glucose forecasts and estimates for our cohort using the Houlihan-selected parameter sets generally also minimize forecasting errors compared to other parameter selection methods such as by-hand parameter selection. Nevertheless, the forecast with the lowest forecast error does not always accurately represent physiology, but further advancements of the algorithm provide a path for improving physiologic fidelity as well. Our hope is that this methodology represents a first step toward combining machine learning with data assimilation and provides a lower-threshold entry point for using data assimilation with clinical data by helping select the right parameters to estimate
An End-to-End Semantic Platform for Nutritional Diseases Management
The self-management of nutritional diseases requires a system that combines food tracking with the potential risks of food categories on people’s health based on their personal health records (PHRs). The challenges range from the design of an effective food image classification strategy to the development of a full-fledged knowledge-based system. This maps the results of the classification strategy into semantic information that can be exploited for reasoning. However, current works mainly address the single challenges separately without their integration into a whole pipeline. In this paper, we propose a new end-to-end semantic platform where: (i) the classification strategy aims to extract food categories from food pictures; (ii) an ontology is used for detecting the risk factors of food categories for specific diseases; (iii) the Linked Open Data (LOD) Cloud is queried for extracting information concerning related diseases and comorbidities; and, (iv) information from the users’ PHRs are exploited for generating proper personal feedback. Experiments are conducted on a new publicly released dataset. Quantitative and qualitative evaluations, from two living labs, demonstrate the effectiveness and the suitability of the proposed approach
Trackly:A Customisable and Pictorial Self-Tracking App to Support Agency in Multiple Sclerosis Self-Care
Self-tracking is an important part of self-care. However, predefined self-tracking approaches can impede people's agency in managing their health. We investigated a customisable and pictorial self-tracking approach in multiple sclerosis self-management by implementing and conducting a field study of Trackly: a prototype app that supports people in defining and colouring pictorial trackers, such as body shapes. We found that participants utilised the elements of Trackly designed to support agentive behaviour: they defined personally meaningful tracking parameters in their own words, and particularly valued being able to flexibly colour in and make sense of their pictorial trackers. Having been able to support their individual self-care intentions with Trackly, participants reported a spectrum of interrelated experiences of agency, including a sense of ownership, identity, self-awareness, mindfulness, and control. Our findings demonstrate the importance of supporting people's individual needs and creative capacities to foster mindful and personally meaningful engagement with health and wellbeing data