A Review of Wearable Multi-Wavelength Photoplethysmography.

Optical pulse detection 'photoplethysmography' (PPG) provides a means of low cost and unobtrusive physiological monitoring that is popular in many wearable devices. However, the accuracy, robustness and generalizability of single-wavelength PPG sensing are sensitive to biological characteristics as well as sensor configuration and placement; this is significant given the increasing adoption of single-wavelength wrist-worn PPG devices in clinical studies and healthcare. Since different wavelengths interact with the skin to varying degrees, researchers have explored the use of multi-wavelength PPG to improve sensing accuracy, robustness and generalizability. This paper contributes a novel and comprehensive state-of-the-art review of wearable multi-wavelength PPG sensing, encompassing motion artifact reduction and estimation of physiological parameters. The paper also encompasses theoretical details about multi-wavelength PPG sensing and the effects of biological characteristics. The review findings highlight the promising developments in motion artifact reduction using multi-wavelength approaches, the effects of skin temperature on PPG sensing, the need for improved diversity in PPG sensing studies and the lack of studies that investigate the combined effects of factors. Recommendations are made for the standardization and completeness of reporting in terms of study design, sensing technology and participant characteristics.

Evaluating the clinical decision making of physiotherapists in the assessment and management of paediatric shoulder instability.

OBJECTIVE: To elicit what information and clinical decision-making processes physiotherapists use in the assessment and management of paediatric shoulder instability. DESIGN: Qualitative study. A modified nominal focus group technique, involving three clinical vignettes, was used to elicit physiotherapists' decision-making processes. SETTING: Physiotherapy departments from across four separate clinical sites. SUBJECTS: Twenty-five physiotherapists, (18F:7M), ranging from two to 29 years post qualification. OUTCOMES MEASURES: Thematic analysis. The initial round of coding was used to draw up a quantitative assessment of the diagnoses and map information used for clinical decision-making against the International Classification of Functioning (ICF) framework. RESULTS: The themes identified related to 'Differences in diagnoses, classification and diagnostic processes', 'Diagnostic process occurs over a long period of time', 'Management and prognosis are influenced by a number of factors' and 'Diagnostic test choices and prognosis influenced by factors beyond the patient injury'. CONCLUSION: Current methods of assessment are prone to bias and error and may lead to inconsistent or delayed provision of essential care. Further work is needed to develop methods of measurement and frameworks which can accurately identify relevant physiological mechanisms and personal factors associated with shoulder instability as a part of the assessment/diagnostic process.

A Preliminary Scoping Study of Federated Learning for the Internet of Medical Things.

This paper presents a scoping review of federated learning for the Internet of Medical Things (IoMT) and demonstrates the limited amount of research work in an area which has potential to improve patient care. Federated Learning and IoMT - as standalone technologies - have already proved to be highly disruptive but there is a need for further research to apply federated learning to the IoMT.

Quantifying Missingness in Wearable Heart Rate Recordings.

Wrist-worn photoplethysmography (PPG) heart rate monitoring devices are increasingly used in clinical applications despite the potential for data missingness and inaccuracy. This paper provides an analysis of the intermittency of experimental wearable data recordings. Devices recorded heart rate with gaps of 5 or more minutes 41.6% of the time and 15 or more minutes 3.8% of the time.

Implications for the design of a Diagnostic Decision Support System (DDSS) to reduce time and cost to diagnosis in paediatric shoulder instability.

BACKGROUND: Currently the diagnosis of shoulder instability, particularly in children, is difficult and can take time. These diagnostic delays can lead to poorer outcome and long-term complications. A Diagnostic Decision Support System (DDSS) has the potential to reduce time to diagnosis and improve outcomes for patients. The aim of this study was to develop a concept map for a future DDSS in shoulder instability. METHODS: A modified nominal focus group technique, involving three clinical vignettes, was used to elicit physiotherapists decision-making processes. RESULTS: Twenty-five physiotherapists, (18F:7 M) from four separate clinical sites participated. The themes identified related to 'Variability in diagnostic processes and lack of standardised practice' and 'Knowledge and attitudes towards novel technologies for facilitating assessment and clinical decision making'. CONCLUSION: No common structured approach towards assessment and diagnosis was identified. Lack of knowledge, perceived usefulness, access and cost were identified as barriers to adoption of new technology. Based on the information elicited a conceptual design of a future DDSS has been proposed. Work to develop a systematic approach to assessment, classification and diagnosis is now proposed. Trial Registraty This was not a clinical trial and so no clinical trial registry is needed.

Investigation of wearable health tracker version updates.

BACKGROUND: Wearable fitness trackers are increasingly used in healthcare applications; however, the frequent updating of these devices is at odds with traditional medical device practices. OBJECTIVE: Our objective was to explore the nature and frequency of wearable tracker updates recorded in device changelogs, to reveal the chronology of updates and to estimate the intervals where algorithm updates could impact device validations. METHOD: Updates for devices meeting selection criteria (that included their use in clinical trials) were independently labelled by four researchers according to simple function and specificity schema. RESULTS: Device manufacturers have diverse approaches to update reporting and changelog practice. Visual representations of device changelogs reveal the nature and chronology of device iterations. 13% of update items were unspecified and 32% possibly affected validations with as few as 5 days between updates that may affect validation. CONCLUSION: Manufacturers could aid researchers and health professionals by providing more informative device update changelogs.

Version Reporting and Assessment Approaches for New and Updated Activity and Heart Rate Monitors.

This paper addresses the significant need for improvements in device version reporting and practice across the academic and technical activity monitoring literature, and it recommends assessments for new and updated consumer sensing devices. Reproducibility and data veracity are central to good scholarship, and particularly significant in clinical and health applications. Across the literature there is an absence of device version reporting and a failure to recognize that device validity is not maintained when firmware and software updates can, and do, change device performance and parameter estimation. In this paper, we propose the use of tractable methods to assess devices at their current version and provide an example empirical approach. Experimental results for heart rate and step count acquisitions during walking and everyday living activities from Garmin Vivosmart 3 (v4.10) wristband monitors are presented and analyzed, and the reliability issues of optically-acquired heart rates, especially during periods of activity, are demonstrated and discussed. In conclusion, the paper recommends the empirical assessment of new and updated activity monitors and improvements in device version reporting across the academic and technical literature.

Evaluation of AllergiSense Smartphone Tools for Adrenaline Injection Training.

Anaphylaxis is an increasingly prevalent life-threatening allergic condition that requires people with anaphylaxis and their caregivers to be trained in the avoidance of allergen triggers and in the administration of adrenaline autoinjectors. The prompt and correct administration of autoinjectors in the event of an anaphylactic reaction is a significant challenge in the management of anaphylaxis. Unfortunately, many people do not know how to use autoinjectors and either fail to use them or fail to use them correctly. This is due in part to deficiencies in training and also to the lack of a system encouraging continuous practice with feedback. Assistive smartphone healthcare technologies have demonstrated potential to support the management of chronic conditions such as diabetes and cardiovascular disease, but there have been deficiencies in their evaluation and there has been a lack of application to anaphylaxis. This paper describes AllergiSense, a smartphone app and sensing system for anaphylaxis management, and presents the results of a randomized, controlled, prepost evaluation of AllergiSense injection training and feedback tools with healthy participants. Participants whose training was supplemented with AllergiSense injection feedback achieved significantly better practiced injections with 90.5% performing correct injections compared to only 28.6% in the paper-only control group. In addition, the results provide insights into possible self-efficacy failings in traditional training and the benefits of embedding self-efficacy theory into the technology design process.

Effect of chair types on work-related musculoskeletal discomfort during vaginal surgery.

BACKGROUND: Evidence supports that surgeons are at high risk for work-related musculoskeletal disorders. OBJECTIVE: The objective of the study was to compare the effect of different chairs on work-related musculoskeletal discomfort for surgeons during vaginal operations. STUDY DESIGN: This crossover study randomly assigned 4 surgeons to 4 chair types using a 4 × 4 Latin square model: a conventional round stool, a round stool with a backrest, a saddle chair with a backrest, and a Capisco chair. Subjective assessments of surgeon discomfort were performed with a validated body discomfort survey, and workload was assessed with the surgical task load index. The objective postural load was quantified with inertial measurement units of the modified rapid upper limb assessment limits. Subjective and objective assessments of chair comfort were performed with an 11 point scale and seat interface pressure-mapped distributions, respectively. The primary outcome was the difference in body discomfort scores between pre- and postsurgery measurements. Secondary outcomes were the differences in chair comfort scores, postural load, and seating interface pressure-mapped distribution. For each outcome, comparisons among the chair types were based on fitting a linear mixed model that handled the surgeon as a random effect and the chair type as a fixed effect. RESULTS: Data were collected for 48 vaginal procedures performed for pelvic organ prolapse. Mean (SD) duration of surgery was 122.3 (25.1) minutes. Surgeons reported body discomfort during 31 procedures (67.4%). Subjective increase in discomfort from the preoperative state was noted most commonly in the lower back (n = 14, 30.4%), followed by right shoulder (n = 12, 26.1%), upper back (n = 8, 17.4%), hips and buttocks (n = 7, 15.2%), left shoulder (n = 6, 13.0%), right or left thigh (n = 6, 13.0%), and neck (n = 6, 13.0%). Pre- and postsurgery body discomfort scores did not differ with respect to chair type. Chair discomfort scores for the round stool and the saddle chair were significantly higher than the round stool with backrest and the Capisco chair (P < .001). Although the average modified rapid upper limb assessment postural scores showed moderate to high musculoskeletal risk of neck and shoulder discomfort across the 4 surgeons; chair type did not affect postural scores. The saddle chair had significantly reduced dispersion of seated pressure vs the round stool with backrest (P ≤ .001), depicted by the number of cells with pressure values >5 mm Hg. An increased dispersion of pressure across the chair surface was associated with increased comfort (Spearman correlation, 0.40, P = .006). CONCLUSION: Musculoskeletal strain and associated discomfort for surgeons are very high during vaginal operations. Chair type can affect comfort, and chairs with more uniform distribution and fewer pressure points are more comfortable. However, the chair type used in surgery did not influence the musculoskeletal postural load findings.

Work-related musculoskeletal disorders among vaginal surgeons.

INTRODUCTION AND HYPOTHESIS: Work-related musculoskeletal disorders (MSDs) reportedly affect a large proportion of providers in obstetrics and gynecology. We hypothesize a high MSD prevalence rate among vaginal surgeons associated with surgeon- and work-related characteristics. METHODS: Surveys were distributed to members of the International Urogynecological Association and American Urogynecological Society. Exclusion criteria included inability to read English, no computer access, invalid or unavailable e-mail address, and missing >50% of responses. RESULTS: Among respondents, 86.7% (436/503) reported ever having work-related MSDs. On univariate analysis, surgeons involved in surgical teaching were significantly more likely to report work-related MSDs. Female surgeons had more frequent and more severe MSDs in the neck, dominant shoulder, and upper back. Older age and more years of work experience were associated with seeking medical attention. Right-hand dominance was associated with negative consequences on work behavior. CONCLUSIONS: A large proportion of vaginal surgeon respondents reported work-related MSDs.

Comparison of required operating forces between floor-based and overhead-mounted patient lifting devices.

This study investigated the differences in required push, pull and rotating forces for moving fully loaded, floor-based and overhead-mounted full body patient lifting devices with simulated patients of varying weight on a floor of optimal design (i.e. level vinyl tile over concrete). A single person operated the lifting devices for all of the tests. Eighteen male and female volunteer participants, ranging in weight from 51 to 146 kg, acted as patients during the lifting tests. For each test, the simulated patients were pushed and pulled for 3.7 linear metres and were rotated while sitting in the lift slings. Force measurements were acquired using two single axis dynamometers affixed to the lifting devices. Results revealed that, in general, operator input force and torque increased with patient weight category and floor-based lifts required greater force and torque compared to the overhead-mounted lift. Comparison of the required forces with published force limits reveals that the required push and pull force from the various patient lift systems, across all weight categories, were generally acceptable to 90% of the female population. The required forces for these patient transfer tasks, however, could exceed maximum acceptable force limits if the floor surfaces were less than ideal, such as floors composed of carpet, wood, or inclined surfaces. Additional research is needed to assess these conditions.

A wavelet-based region of interest encoder for the compression of angiogram video sequences.

A new method for the compression of angiogram video sequences is presented. The method is based on the philosophy that diagnostically significant areas of the image should be allocated the greatest proportion of the total allocated bit budget. The approach uses a three-dimensional wavelet-coder based on the popular set partitioning in hierarchical trees algorithm. Incorporated into this framework are a region-of-interest (ROI) detection stage and a texture-modeling stage. The combined result is an approach that models the high-frequency wavelet coefficients for some diagnostically unimportant regions of the image in an extremely efficient manner. This allows additional bits to be used within the ROI to improve the quality of the diagnostically significant areas. Results are compared for a number of real data sets and evaluated by trained cardiologists.

The effect of dynamic versus isometric resistance training on pain and functioning among adults with osteoarthritis of the knee.

OBJECTIVE: To compare 16 weeks of isometric versus dynamic resistance training versus a control on knee pain and functioning among patients with knee osteoarthritis (OA). DESIGN: Randomized clinical trial. SETTING: Outpatient setting. PARTICIPANTS: A total of 102 volunteer subjects with OA of the knee randomized to isometric (n=32) and dynamic (n=35) resistance training groups or a control (n=35). INTERVENTIONS: Strength exercises for the legs, 3 times weekly for 16 weeks. Dynamic group: exercises across a functional range of motion; isometric: exercises at discrete joint angles. MAIN OUTCOME MEASURES: The time to descend and ascend a flight of 27 stairs and to get down and up off of the floor. Knee pain was assessed immediately after each functional task. The Western Ontario and McMaster Universities Osteoarthritis Index was used to assess perceived pain, stiffness, and functional ability. RESULTS: In the isometric group, time to perform all 4 functional tasks decreased (P<.05) by 16% to 23%. In the dynamic group, time to descend and ascend stairs decreased by 13% to 17%. Both groups decreased knee pain while performing the functional tasks by 28% to 58%. Other measures of pain and functioning were significantly and favorably affected in the training groups. The improvements in the 2 training groups as a result of their respective therapies were not significantly different. The control group did not change over the duration of the study. CONCLUSION: Dynamic or isometric resistance training improves functional ability and reduces knee joint pain of patients with knee OA.