An interpretable health behavioral intervention policy for mobile device users.

An increasing number of people use mobile devices to monitor their behavior, such as exercise, and record their health status, such as psychological stress. However, these devices rarely provide ongoing support to help users understand how their behavior contributes to changes in their health status. To address this challenge, we aim to develop an interpretable policy for physical activity recommendations that reduce a user's perceived psychological stress, over a given time horizon. We formulate this problem as a sequential decision-making problem and solve it using a new method that we refer to as threshold Q-learning (TQL). The advantage of the TQL method over traditional Q-learning is that it is "doubly robust" and interpretable. This interpretability is achieved by making model assumptions and incorporating threshold selection into the learning process. Our simulation results indicate that the TQL method performs better than the Q-learning method given model misspecification. Our analyses are performed on data collected from 79 healthy adults over a 7 week period, where the data comprise physical activity patterns collected from mobile devices and self-assessed stress levels of the users. This work serves as a first step toward a computational health coaching solution for mobile device users.

Present and Future Trends in Consumer Health Informatics and Patient-Generated Health Data.

Objectives: Consumer Health Informatics (CHI) and the use of Patient-Generated Health Data (PGHD) are rapidly growing focus areas in healthcare. The objective of this paper is to briefly review the literature that has been published over the past few years and to provide a sense of where the field is going. Methods: We searched PubMed and the ACM Digital Library for articles published between 2014 and 2016 on the topics of CHI and PGHD. The results of the search were screened for relevance and categorized into a set of common themes. We discuss the major topics covered in these articles. Results: We retrieved 65 articles from our PubMed query and 32 articles from our ACM Digital Library query. After a review of titles, we were left with 47 articles to conduct our full article survey of the activities in CHI and PGHD. We have summarized these articles and placed them into major categories of activity. Within the domain of consumer health informatics, articles focused on mobile health and patient-generated health data comprise the majority of the articles published in recent years. Conclusions: Current evidence indicates that technological advancements and the widespread availability of affordable consumer-grade devices are fueling research into using PGHD for better care. As we observe a growing number of (pilot) developments using various mobile health technologies to collect PGHD, major gaps still exist in how to use the data by both patients and providers. Further research is needed to understand the impact of PGHD on clinical outcomes.

Added Value from Secondary Use of Person Generated Health Data in Consumer Health Informatics.

Introduction: Various health-related data, subsequently called Person Generated Health Data (PGHD), is being collected by patients or presumably healthy individuals as well as about them as much as they become available as measurable properties in their work, home, and other environments. Despite that such data was originally just collected and used for dedicated predefined purposes, more recently it is regarded as untapped resources that call for secondary use. Method: Since the secondary use of PGHD is still at its early evolving stage, we have chosen, in this paper, to produce an outline of best practices, as opposed to a systematic review. To this end, we identified key directions of secondary use and invited protagonists of each of these directions to present their takes on the primary and secondary use of PGHD in their sub-fields. We then put secondary use in a wider perspective of overarching themes such as privacy, interpretability, interoperability, utility, and ethics. Results: We present the primary and secondary use of PGHD in four focus areas: (1) making sense of PGHD in augmented Shared Care Plans for care coordination across multiple conditions; (2) making sense of PGHD from patient-held sensors to inform cancer care; (3) fitting situational use of PGHD to evaluate personal informatics tools in adaptive concurrent trials; (4) making sense of environment risk exposure data in an integrated context with clinical and omics-data for biomedical research. Discussion: Fast technological progress in all the four focus areas calls for a societal debate and decision-making process on a multitude of challenges: how emerging or foreseeable results transform privacy; how new data modalities can be interpreted in light of clinical data and vice versa; how the sheer mass and partially abstract mathematical properties of the achieved insights can be interpreted to a broad public and can consequently facilitate the development of patient-centered services; and how the remaining risks and uncertainties can be evaluated against new benefits. This paper is an initial summary of the status quo of the challenges and proposals that address these issues. The opportunities and barriers identified can serve as action items individuals can bring to their organizations when facing challenges to add value from the secondary use of patient-generated health data.

A quantitative recipe for engineering protein polymer nanoparticles.

Protein polymers can assemble switchable nanostructures with emerging applications as biomaterials and nanomedicines. For example, above a critical micelle temperature (CMT) some elastin-like polypeptide (ELP) diblock copolymers assemble spherical nanoparticles, which may modulate cellular internalization and in vivo biodistribution. To achieve engineering-level control over their properties, this report explores a comprehensive library of ELP monoblock and diblock polymers. For the first time, we report that a surprisingly high core molecular weight is required for stable nanoparticle formation; furthermore, nanoparticle size depends on polymer molecular weight. A mathematical model was developed to characterize four ELP monoblock libraries and to predict the phase behavior of corresponding diblock copolymers. The CMT was almost entirely dependent on the hydrophobic core ELP, while the bulk phase transition temperature (Tt,bulk ) depends predominantly on the hydrophilic block. Nanoparticle assembly was accompanied by a conversion in secondary structure of the hydrophobic block from random coil and beta-sheets to type-2 ß turns. For the first time, this report enables the rational design of ELP protein polymer nanoparticles with physico-chemico properties that will be suitable for biological applications.

Clinical characteristics of optic neuritis in Taiwanese children.

PURPOSE: To document the etiology, clinical presentation, and visual prognosis of optic neuritis in Taiwanese children. METHODS: Retrospectively reviewed children younger than 18 years old with optic neuritis in Chang Gung Memorial Hospital and Chang Gung Children's Hospital from 1998 to 2009. RESULTS: There were 24 children (38 eyes) with optic neuritis in that period. Overall, 14 patients (58.3%) were female and 10 patients (41.7%) were male. In total, 14 patients (58.3%) had bilateral involvement, and 10 patients (41.7%) had unilateral involvement. Out of 38 eyes, 24 (63.2%) had disc swelling. Out of 24 patients, 21 (87.5%) underwent intravenous steroid therapy (10 to 30 mg/kg/day) for 3-5 days, and followed by an oral taper. Out of 24 patients, 20 (83.3%) achieved final visual acuity (VA) of 20/40 or better. However, a poor visual outcome (four patients) (VA<20/40) was correlated with pale disc at presentation (P=0.002, Pearson χ (2)-test) and age older than 10 years (P=0.012, Fisher's exact test). Five patients were diagnosed with acute disseminated encephalomyelitis (ADEM) (21%), and three patients were diagnosed with multiple sclerosis (MS) (12.5%). Patients with ADEM did not have a better visual outcome than patients with MS (P=0.643, Fisher's exact test). CONCLUSIONS: Visual recovery from optic neuritis was favorable in Taiwanese children. A poor visual outcome was correlated with pale disc at presentation and patients' age older than 10 years. ADEM is the most common associated systemic disease; MS is relatively rare.