Assessing the Effect of Data Quality on Distance Estimation in Smartphone-Based Outdoor 6MWT.

As a result of technological advancements, functional capacity assessments, such as the 6-minute walk test, can be performed remotely, at home and in the community. Current studies, however, tend to overlook the crucial aspect of data quality, often limiting their focus to idealised scenarios. Challenging conditions may arise when performing a test given the risk of collecting poor-quality GNSS signal, which can undermine the reliability of the results. This work shows the impact of applying filtering rules to avoid noisy samples in common algorithms that compute the walked distance from positioning data. Then, based on signal features, we assess the reliability of the distance estimation using logistic regression from the following two perspectives: error-based analysis, which relates to the estimated distance error, and user-based analysis, which distinguishes conventional from unconventional tests based on users' previous annotations. We highlight the impact of features associated with walked path irregularity and direction changes to establish data quality. We evaluate features within a binary classification task and reach an F1-score of 0.93 and an area under the curve of 0.97 for the user-based classification. Identifying unreliable tests is helpful to clinicians, who receive the recorded test results accompanied by quality assessments, and to patients, who can be given the opportunity to repeat tests classified as not following the instructions.

Optilume drug-coated balloon for anterior urethral stricture: 2-year results of the ROBUST III trial.

Objective: The aim of this study is to report the updated 2-year results of the intervention arm of the ROBUST III randomized trial evaluating the safety and efficacy of the Optilume drug-coated balloon (DCB) versus standard endoscopic management of recurrent male anterior urethral stricture. Materials and Methods: Eligible patients included men with recurrent anterior urethral stricture ≤3 cm in length and ≤12Fr in diameter, International Prostate Symptom Score (IPSS) ≥11 and peak flow rate (Qmax) <15 mL/s. Patients were randomized to treatment with the Optilume DCB or standard-of-care endoscopic management. Primary efficacy endpoints measured at 2 years included freedom from re-intervention and changes in IPSS, Qmax and post-void residual (PVR). Secondary endpoint was impact on sexual function using the International Index of Erectile Function (IIEF). Primary safety endpoint was freedom from serious procedure- or device-related adverse events (AEs). Results: A total of 127 patients enrolled at 22 sites in the United States and Canada (48 randomized to standard-of-care dilation and 79 to DCB dilation). Seventy-five patients in the DCB arm entered the open-label phase after 6 months. Participants averaged 3.2 prior endoscopic interventions (range 2-10); most (89.9%) had bulbar strictures with an average stricture length of 1.63 cm (SD 0.76). Significant improvements in IPSS, average Qmax and PVR were maintained at 2 years. Freedom from repeat intervention was significantly higher in the Optilume DCB arm at 2 years versus the Control arm at 1 year (77.8% vs. 23.6%, p < 0.001). During the follow-up period, there were 15 treatment failures and two non-study-related deaths. Treatment-related AEs were rare and generally self-limited (haematuria, dysuria and urinary tract infection). Conclusion: The Optilume DCB shows sustained improvement in both objective and subjective voiding parameters at 2-year follow-up. Optilume appears to provide a safe and effective endoscopic treatment alternative for short recurrent anterior urethral strictures among men who wish to avoid or delay formal urethroplasty.

Quantifying Parkinson's disease severity using mobile wearable devices and machine learning: the ParkApp pilot study protocol.

INTRODUCTION: The clinical assessment of Parkinson's disease (PD) symptoms can present reliability issues and, with visits typically spaced apart 6 months, can hardly capture their frequent variability. Smartphones and smartwatches along with signal processing and machine learning can facilitate frequent, remote, reliable and objective assessments of PD from patients' homes. AIM: To investigate the feasibility, compliance and user experience of passively and actively measuring symptoms from home environments using data from sensors embedded in smartphones and a wrist-wearable device. METHODS AND ANALYSIS: In an ongoing clinical feasibility study, participants with a confirmed PD diagnosis are being recruited. Participants perform activity tests, including Timed Up and Go (TUG), tremor, finger tapping, drawing and vocalisation, once a week for 2 months using the Mobistudy smartphone app in their homes. Concurrently, participants wear the GENEActiv wrist device for 28 days to measure actigraphy continuously. In addition to using sensors, participants complete the Beck's Depression Inventory, Non-Motor Symptoms Questionnaire (NMSQuest) and Parkinson's Disease Questionnaire (PDQ-8) questionnaires at baseline, at 1 month and at the end of the study. Sleep disorders are assessed through the Parkinson's Disease Sleep Scale-2 questionnaire (weekly) and a custom sleep quality daily questionnaire. User experience questionnaires, Technology Acceptance Model and User Version of the Mobile Application Rating Scale, are delivered at 1 month. Clinical assessment (Movement Disorder Society-Unified Parkinson Disease Rating Scale (MDS-UPDRS)) is performed at enrollment and the 2-month follow-up visit. During visits, a TUG test is performed using the smartphone and the G-Walk motion sensor as reference device. Signal processing and machine learning techniques will be employed to analyse the data collected from Mobistudy app and the GENEActiv and correlate them with the MDS-UPDRS. Compliance and user aspects will be informing the long-term feasibility. ETHICS AND DISSEMINATION: The study received ethical approval by the Swedish Ethical Review Authority (Etikprövningsmyndigheten), with application number 2022-02885-01. Results will be reported in peer-reviewed journals and conferences. Results will be shared with the study participants.

Some Design Considerations in Passive Indoor Positioning Systems.

User location is becoming an increasingly common and important feature for a wide range of services. Smartphone owners increasingly use location-based services, as service providers add context-enhanced functionality such as car-driving routes, COVID-19 tracking, crowdedness indicators, and suggestions for nearby points of interest. However, positioning a user indoors is still problematic due to the fading of the radio signal caused by multipath and shadowing, where both have complex dependencies on the indoor environment. Location fingerprinting is a common positioning method where Radio Signal Strength (RSS) measurements are compared to a reference database of previously stored RSS values. Due to the size of the reference databases, these are often stored in the cloud. However, server-side positioning computations make preserving the user's privacy problematic. Given the assumption that a user does not want to communicate his/her location, we pose the question of whether a passive system with client-side computations can substitute fingerprinting-based systems, which commonly use active communication with a server. We compared two passive indoor location systems based on multilateration and sensor fusion using an Unscented Kalman Filter (UKF) with fingerprinting and show how these may provide accurate indoor positioning without compromising the user's privacy in a busy office environment.

Determination of lithium concentration in capillary blood using volumetric dried blood spots.

BACKGROUND: Lithium is a cornerstone in the treatment of bipolar disorder and is considered one of the most effective treatments in psychiatry at large. Lithium treatment requires individual dosing with frequent serum concentration measurements due to the narrow therapeutic window and risk of toxicity. There is need for patient-centric methods for lithium monitoring and the use of dried blood spots has recently been proposed for determination of lithium concentration. The purpose of the current study was to assess feasibility of this method by introducing a volumetric technique developed for home-sampling. MATERIALS AND METHODS: Laboratory: Capillary blood was sampled by finger-prick using a volumetric device that collects 10 µL volumes as a dried blood spot. Lithium was measured in the dried blood spots using a validated atomic absorption spectroscopy method. CLINICAL: Thirty-nine lithium-treated patients were recruited, and dried blood spots and venous blood samples were collected. Routine serum analysis was performed for comparison. RESULTS: The range of serum lithium concentrations was 0.41-1.22 mmol/L, and the dried blood spot/serum ratio was 0.78. A strong linear correlation between the two specimens was shown with Pearson's R = 0.95 (r2 = 0.90). Adding hematocrit as a variable only minimally improved prediction. CONCLUSION: Volumetric dried blood spots is a promising technique for measurement of lithium concentrations. This will enable home-sampling and could potentially save resources, improve compliance, and make treatment safer. This may facilitate the use of lithium treatment in regions where monitoring via venous blood sampling remains difficult. However, the usability of dried blood spots for monitoring lithium treatment longitudinally remains to be examined.

The Clinical Cell-Cycle Risk (CCR) Score Is Associated With Metastasis After Radiation Therapy and Provides Guidance on When to Forgo Combined Androgen Deprivation Therapy With Dose-Escalated Radiation.

PURPOSE: The clinical cell-cycle risk (CCR) score, which combines the University of California, San Francisco's Cancer of the Prostate Risk Assessment (CAPRA) and the cell cycle progression (CCP) molecular score, has been validated to be prognostic of disease progression for men with prostate cancer. This study evaluated the ability of the CCR score to prognosticate the risk of metastasis in men receiving dose-escalated radiation therapy (RT) with or without androgen deprivation therapy (ADT). METHODS AND MATERIALS: This retrospective, multi-institutional cohort study included men with localized National Comprehensive Cancer Network (NCCN) intermediate-, high-, and very high-risk prostate cancer (N = 741). Patients were treated with dose-escalated RT with or without ADT. The primary outcome was time to metastasis. RESULTS: The CCR score prognosticated metastasis with a hazard ratio (HR) per unit score of 2.22 (95% confidence interval [CI], 1.71-2.89; P < .001). The CCR score better prognosticated metastasis than NCCN risk group (CCR, P < .001; NCCN, P = .46), CAPRA score (CCR, P = .002; CAPRA, P = .59), or CCP score (CCR, P < .001; CCP, P = .59) alone. In bivariable analyses, CCR score remained highly prognostic when accounting for ADT versus no ADT (HR, 2.18; 95% CI, 1.61-2.96; P < .001), ADT duration as a continuous variable (HR, 2.11; 95% CI, 1.59-2.79; P < .001), or ADT given at or below the recommended duration for each NCCN risk group (HR, 2.19; 95% CI, 1.69-2.86; P < .001). Men with CCR scores below or above the multimodality threshold (CCR score, 2.112) had a 10-year risk of metastasis of 3.7% and 21.24%, respectively. Men with below-threshold scores receiving RT alone had a 10-year risk of metastasis of 3.7%, and for men receiving RT plus ADT, the 10-year risk of metastasis was also 3.7%. CONCLUSIONS: The CCR score accurately and precisely prognosticates metastasis and adds clinically actionable information relative to guideline-recommended therapies based on NCCN risk in men undergoing dose-escalated RT with or without ADT. For men with scores below the multimodality threshold, adding ADT may not significantly reduce their 10-year risk of metastasis.

One-Year Results for the ROBUST III Randomized Controlled Trial Evaluating the Optilume® Drug-Coated Balloon for Anterior Urethral Strictures.

PURPOSE: The Optilume® drug-coated balloon (DCB) is a urethral dilation balloon with a paclitaxel coating that combines mechanical dilation for immediate symptomatic relief with local drug delivery to maintain urethral patency. The ROBUST III study is a randomized, single-blind trial evaluating the safety and efficacy of the Optilume DCB against endoscopic management of recurrent anterior urethral strictures. MATERIALS AND METHODS: Eligible patients were adult males with anterior strictures ≤12Fr in diameter and ≤3 cm in length, at least 2 prior endoscopic treatments, International Prostate Symptom Score ≥11 and maximum flow rate <15 ml per second. A total of 127 subjects were enrolled at 22 sites. The primary study end point was anatomical success (≥14Fr by cystoscopy or calibration) at 6 months. Key secondary end points included freedom from repeat treatment, International Prostatic Symptom Score and peak flow rate. The primary safety end point included freedom from serious device- or procedure-related complications. RESULTS: Baseline characteristics were similar between groups, with subjects having an average of 3.6 prior treatments and average length of 1.7 cm. Anatomical success for Optilume DCB was significantly higher than control at 6 months (75% vs 27%, p <0.001). Freedom from repeat intervention was significantly higher in the Optilume DCB arm. Immediate symptom and urinary flow rate improvement was significant in both groups, with the benefit being more durable in the Optilume DCB group. The most frequent adverse events included urinary tract infection, post-procedural hematuria and dysuria. CONCLUSIONS: The results of this randomized controlled trial support that Optilume is safe and superior to standard direct vision internal urethrotomy/dilation for the treatment of recurrent anterior urethral strictures <3 cm in length. The Optilume DCB may serve as an important alternative for men who have had an unsuccessful direct vision internal urethrotomy/dilation but want to avoid or delay urethroplasty.

Enzalutamide versus bicalutamide in patients with nonmetastatic castration-resistant prostate cancer: a prespecified subgroup analysis of the STRIVE trial.

BACKGROUND: In the phase 2, randomized, double-blind STRIVE trial, enzalutamide significantly reduced the risk of prostate cancer progression or death versus bicalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) and nonmetastatic CRPC (nmCRPC). The objective of this protocol-specified subgroup analysis of STRIVE was to investigate the benefit of enzalutamide versus bicalutamide specifically in patients with nmCRPC. METHODS: Patients (N = 139) were stratified by disease stage and randomized to enzalutamide 160 mg/day plus androgen deprivation therapy (ADT; n = 70) or bicalutamide 50 mg/day plus ADT (n = 69). RESULTS: Baseline characteristics of patients with nmCRPC were comparable between groups. At a median of 17 months follow-up, enzalutamide reduced the risk of progression or death by 76% versus bicalutamide in patients with nmCRPC (hazard ratio [HR], 0.24; 95% CI 0.14-0.42). Enzalutamide reduced risk of prostate-specific antigen progression by 82% versus bicalutamide in patients with nmCRPC (HR, 0.18; 95% CI 0.10-0.34). The most frequently reported adverse events by patients receiving enzalutamide were fatigue (36.2%), hot flush (20.3%), decreased appetite (17.4%), dizziness (17.4%), and nausea (17.4%). CONCLUSIONS: This STRIVE subgroup analysis of patients with nmCRPC illustrates the benefit of enzalutamide in reducing the risk of progression or death versus bicalutamide in patients with nmCRPC. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01664923.

Synthetic Generation of Passive Infrared Motion Sensor Data Using a Game Engine.

Quantifying the number of occupants in an indoor space is useful for a wide variety of applications. Attempts have been made at solving the task using passive infrared (PIR) motion sensor data together with supervised learning methods. Collecting a large labeled dataset containing both PIR motion sensor data and ground truth people count is however time-consuming, often requiring one hour of observation for each hour of data gathered. In this paper, a method is proposed for generating such data synthetically. A simulator is developed in the Unity game engine capable of producing synthetic PIR motion sensor data by detecting simulated occupants. The accuracy of the simulator is tested by replicating a real-world meeting room inside the simulator and conducting an experiment where a set of choreographed movements are performed in the simulated environment as well as the real room. In 34 out of 50 tested situations, the output from the simulated PIR sensors is comparable to the output from the real-world PIR sensors. The developed simulator is also used to study how a PIR sensor's output changes depending on where in a room a motion is carried out. Through this, the relationship between sensor output and spatial position of a motion is discovered to be highly non-linear, which highlights some of the difficulties associated with mapping PIR data to occupancy count.

Rotation Averaging with the Chordal Distance: Global Minimizers and Strong Duality.

In this paper we explore the role of duality principles within the problem of rotation averaging, a fundamental task in a wide range of applications. In its conventional form, rotation averaging is stated as a minimization over multiple rotation constraints. As these constraints are non-convex, this problem is generally considered challenging to solve globally. We show how to circumvent this difficulty through the use of Lagrangian duality. While such an approach is well-known it is normally not guaranteed to provide a tight relaxation. Based on spectral graph theory, we analytically prove that in many cases there is no duality gap unless the noise levels are severe. This allows us to obtain certifiably global solutions to a class of important non-convex problems in polynomial time. We also propose an efficient, scalable algorithm that outperforms general purpose numerical solvers by a large margin and compares favourably to current state-of-the-art. Further, our approach is able to handle the large problem instances commonly occurring in structure from motion settings and it is trivially parallelizable. Experiments are presented for a number of different instances of both synthetic and real-world data.

Privacy Personas for IoT-Based Health Research: A Privacy Calculus Approach.

The reliance on data donation from citizens as a driver for research, known as citizen science, has accelerated during the Sars-Cov-2 pandemic. An important enabler of this is Internet of Things (IoT) devices, such as mobile phones and wearable devices, that allow continuous data collection and convenient sharing. However, potentially sensitive health data raises privacy and security concerns for citizens, which research institutions and industries must consider. In e-commerce or social network studies of citizen science, a privacy calculus related to user perceptions is commonly developed, capturing the information disclosure intent of the participants. In this study, we develop a privacy calculus model adapted for IoT-based health research using citizen science for user engagement and data collection. Based on an online survey with 85 participants, we make use of the privacy calculus to analyse the respondents' perceptions. The emerging privacy personas are clustered and compared with previous research, resulting in three distinct personas which can be used by designers and technologists who are responsible for developing suitable forms of data collection. These are the 1) Citizen Science Optimist, the 2) Selective Data Donor, and the 3) Health Data Controller. Together with our privacy calculus for citizen science based digital health research, the three privacy personas are the main contributions of this study.

Weighted Gleason Grade Group (WGGG): A new prostate cancer biopsy reporting system with prognostic potential.

INTRODUCTION: Presently, prostate biopsy (PBx) results report the highest Gleason Grade Group (GGG) as a single metric that gauges the overall clinical aggressiveness of cancer and dictates treatment. We hypothesized a PBx showing multiple cores of cancer with more volume cancer per core would represent more aggressive disease. We propose the Weighted Gleason Grade Group (WGGG), a novel scoring system that synthesizes all histopathologic data and cancer volume into a single numeric value representing the entire PBx, allowing for improved prediction of adverse pathology and risk of biochemical recurrence (BCR) following radical prostatectomy (RP). METHODS: We studied 171 men who underwent RP after standard PBx. The WGGG was calculated by summing each positive core using the formula: GGG + (GGG x %Ca/core). RP pathology was evaluated for extraprostatic extension (EPE), positive surgical margins (PSM), seminal vesicle invasion (SVI), and lymph node involvement (LNI), and patients were followed for BCR. We compared GGG vs. WGGG receiver operating characteristic curves for each outcome, and determined the predictive capability of GGG and WGGG to identify patients with BCR. Categorized WGGG groups were created based on risk of BCR using classification and regression tree analysis. We then sought to externally validate WGGG in a cohort of 389 patients in a separate institutional dataset. RESULTS: In the development cohort, area under the curves (AUCs) for the WGGG vs. GGG were significantly higher for predicting EPE (0.784 vs. 0.690, P = 0.002), SVI (AUC 0.823 vs. 0.721, P = .014), LNI (AUC 0.862 vs. 0.823, P = 0.039), and PSM (AUC 0.638 vs. 0.575, P = 0.031. Analysis of the validation cohort showed similar findings for EPE (AUC 0.764 vs. 0.729, P = 0.13), SVI (AUC 0.819 vs. 0.749, P = 0.01), LNI (AUC 0.939 vs. 0.867, P = 0.02), and PSM (AUC 0.624 vs. 0.547, P = 0.04). Patients with WGGG >30 (high-risk group) demonstrated ∼50% failure at 2 years in both cohorts. CONCLUSIONS: The WGGG, by providing a metric reflecting the entirety of the PBx, is more informative than conventional single GGG alone in identifying adverse pathologic outcomes and risk of BCR following RP. This superior discriminatory capability has been achieved without any consideration of other commonly available clinical disease characteristics.

Implementation of multiparametric magnetic resonance imaging technology for evaluation of patients with suspicion for prostate cancer in the clinical practice setting.

OBJECTIVES: To investigate the impact of implementing magnetic resonance imaging (MRI) and ultrasonography fusion technology on biopsy and prostate cancer (PCa) detection rates in men presenting with clinical suspicion for PCa in the clinical practice setting. PATIENTS AND METHODS: We performed a review of 1 808 consecutive men referred for elevated prostate-specific antigen (PSA) level between 2011 and 2014. The study population was divided into two groups based on whether MRI was used as a risk stratification tool. Univariable and multivariable analyses of biopsy rates and overall and clinically significant PCa detection rates between groups were performed. RESULTS: The MRI and PSA-only groups consisted of 1 020 and 788 patients, respectively. A total of 465 patients (45.6%) in the MRI group and 442 (56.1%) in the PSA-only group underwent biopsy, corresponding to an 18.7% decrease in the proportion of patients receiving biopsy in the MRI group (P < 0.001). Overall PCa (56.8% vs 40.7%; P < 0.001) and clinically significant PCa detection (47.3% vs 31.0%; P < 0.001) was significantly higher in the MRI vs the PSA-only group. In logistic regression analyses, the odds of overall PCa detection (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.29-2.35; P < 0.001) and clinically significant PCa detection (OR 2.04, 95% CI 1.48-2.80; P < 0.001) were higher in the MRI than in the PSA-only group after adjusting for clinically relevant PCa variables. CONCLUSION: Among men presenting with clinical suspicion for PCa, addition of MRI increases detection of clinically significant cancers while reducing prostate biopsy rates when implemented in a clinical practice setting.

Histologic Changes in Prostate Cancer Detected Subsequent to the 2012 United States Preventive Services Task Force (USPSTF) Prostate Cancer Screening Recommendation.

We report changes in the histopathology of prostate cancer diagnosed in a large urology group practice after the final United States Preventive Services Task Force (USPSTF) Grade D recommendation against prostate-specific antigen screening. All prostate biopsies performed from 2011 through 2015 in a large urology group practice were retrospectively reviewed; 2012 was excluded as a transition year. The changes in biopsy data in years following the USPSTF decision (2013-2015) were then compared with baseline (2011). A total of 10,944 biopsies were evaluated during the study period. Positive biopsy rates rose from 39.1% at baseline to 45.2% in 2015 (P < 0.01) with a marked shift toward more aggressive cancer throughout the study period. The absolute number of patients presenting with Gleason Grade Group 4 or 5 increased from 155/year at baseline to 231, 297, and 285 in 2013, 2014, and 2015, respectively (P < 0.05), unrelated to age or racial changes over time. Black men represented 16% of the cohort. Since the USPSTF recommendation against prostate cancer screening, trends toward a substantial upward grade migration and increased volume of cancers were noted in a cohort of nearly 11,000 patients in a real-world clinical practice. Additionally, continuing reductions in cancer detection in the United States may exacerbate these trends.