Preliminary Study of Vibrotactile Feedback during Home-Based Balance and Coordination Training in Individuals with Cerebellar Ataxia.

Intensive balance and coordination training is the mainstay of treatment for symptoms of impaired balance and mobility in individuals with hereditary cerebellar ataxia. In this study, we compared the effects of home-based balance and coordination training with and without vibrotactile SA for individuals with hereditary cerebellar ataxia. Ten participants (five males, five females; 47 ± 12 years) with inherited forms of cerebellar ataxia were recruited to participate in a 12-week crossover study during which they completed two six-week blocks of balance and coordination training with and without vibrotactile SA. Participants were instructed to perform balance and coordination exercises five times per week using smartphone balance trainers that provided written, graphic, and video guidance and measured trunk sway. The pre-, per-, and post-training performance were assessed using the Scale for the Assessment and Rating of Ataxia (SARA), SARAposture&gait sub-scores, Dynamic Gait Index, modified Clinical Test of Sensory Interaction in Balance, Timed Up and Go performed with and without a cup of water, and multiple kinematic measures of postural sway measured with a single inertial measurement unit placed on the participants' trunks. To explore the effects of training with and without vibrotactile SA, we compared the changes in performance achieved after participants completed each six-week block of training. Among the seven participants who completed both blocks of training, the change in the SARA scores and SARAposture&gait sub-scores following training with vibrotactile SA was not significantly different from the change achieved following training without SA (p>0.05). However, a trend toward improved SARA scores and SARAposture&gait sub-scores was observed following training with vibrotactile SA; compared to their pre-vibrotacile SA training scores, participants significantly improved their SARA scores (mean=−1.21, p=0.02) and SARAposture&gait sub-scores (mean=−1.00, p=0.01). In contrast, no significant changes in SARA scores and SARAposture&gait sub-scores were observed following the six weeks of training without SA compared to their pre-training scores immediately preceding the training block without vibrotactile SA (p>0.05). No significant changes in trunk kinematic sway parameters were observed as a result of training (p>0.05). Based on the findings from this preliminary study, balance and coordination training improved the participants' motor performance, as captured through the SARA. Vibrotactile SA may be a beneficial addition to training regimens for individuals with hereditary cerebellar ataxia, but additional research with larger sample sizes is needed to assess the significance and generalizability of these findings.

Use of three-dimensional printing for adapting and optimizing smartphone ophthalmoscopy to existing SD-OCT instrumentation for rodent and teleost ocular research.

Use of animal models for human vision research is now pervasive. To address a range of technical challenges, laboratories either modify existing equipment or purchase products that are purpose designed. Three-dimensional (3D) printing technology now allows the do-it-yourself capability to invent, innovate, and manufacture for a specific purpose. Ophthalmic imaging is often used with a range of other sophisticated experimental retinal imaging techniques, such as spectral domain optical coherence tomography (SD-OCT). The handheld smartphone camera and cost-effective, readily available professional-quality apps now allow accessible high-definition video ophthalmic image recording. However, to our knowledge, there are few reports of adapting smartphone ophthalmic imaging to existing experimental SD-OCT imaging instrumentation. This would offer better accuracy, reproducibility, and most importantly, precision. The objective of the present study was to use 3D printing to enhance the functionality and precision of existing SD-OCT instrumentation and smartphone-based ophthalmic imaging through construction of a custom 3D-printed assembly. The assembly can be controlled either manually or by the highly precise rodent stage of the SD-OCT instrument. Using this technical approach, 3D printing facilitated a novel methodology for high-quality ophthalmic imaging with low cost and ease of production either manually or by enhancing existing SD-OCT instrumentation.

Compressive recovery of smartphone RGB spectral sensitivity functions.

Spectral response (or sensitivity) functions of a three-color image sensor (or trichromatic camera) allow a mapping from spectral stimuli to RGB color values. Like biological photosensors, digital RGB spectral responses are device dependent and significantly vary from model to model. Thus, the information on the RGB spectral response functions of a specific device is vital in a variety of computer vision as well as mobile health (mHealth) applications. Theoretically, spectral response functions can directly be measured with sophisticated calibration equipment in a specialized laboratory setting, which is not easily accessible for most application developers. As a result, several mathematical methods have been proposed relying on standard color references. Typical optimization frameworks with constraints are often complicated, requiring a large number of colors. We report a compressive sensing framework in the frequency domain for accurately predicting RGB spectral response functions only with several primary colors. Using a scientific camera, we first validate the estimation method with direct spectral sensitivity measurements and ensure that the root mean square errors between the ground truth and recovered RGB spectral response functions are negligible. We further recover the RGB spectral response functions of smartphones and validate with an expanded color checker reference. We expect that this simple yet reliable estimation method of RGB spectral sensitivity can easily be applied for color calibration and standardization in machine vision, hyperspectral filters, and mHealth applications that capitalize on the built-in cameras of smartphones.

The Functionality, Evidence, and Privacy Issues Around Smartphone Apps for the Top Neuropsychiatric Conditions.

OBJECTIVE: There are more than 325,000 health-related smartphone applications (apps) on the market. To better understand the apps currently on the market for the five most disabling neuropsychiatric conditions, the authors conducted a study investigating their intended uses (target population and intervention), the data collected, and any privacy policies. METHODS: This was a cross-sectional study of apps for the five most disabling neuropsychiatric conditions per the World Health Organization: stroke, migraine, depression, Alzheimer's disease and dementia, and anxiety. Up to 15 apps in the U.S. Google Play and Apple app stores were selected based on the following prespecified inclusion criteria: the app appeared in the top 50 search results, offered intervention or tracking capabilities, and listed the condition in the app title or description. Exclusion criteria were <$5.00 to purchase, solely motor versus cognitive-based intervention, or designed for use by caregivers or health care providers. Data abstracted included function, behavior change rewards, and information about intervention, privacy policy, and payment. RESULTS: Eighty-three apps were reviewed (stroke, N=8; migraine, N=25; Alzheimer's disease and dementia, N=8; depression, N=7; anxiety, N=14; apps targeting depression and anxiety, N=21). Sixty-nine percent of apps had an intervention component, 18% were deemed evidence based, 77% had a privacy policy, 70% required payment for access to all features, and 19% rewarded user behavior changes. CONCLUSIONS: Most apps on the market targeted migraine, depression, and anxiety and contained interventions, although most of the interventions did not appear to be evidence based. Additionally, although most apps had privacy policies, lay people may have difficulty understanding these policies due to their complexities.

Recent trends in smartphone-based detection for biomedical applications: a review.

Smartphone-based imaging devices (SIDs) have shown to be versatile and have a wide range of biomedical applications. With the increasing demand for high-quality medical services, technological interventions such as portable devices that can be used in remote and resource-less conditions and have an impact on quantity and quality of care. Additionally, smartphone-based devices have shown their application in the field of teleimaging, food technology, education, etc. Depending on the application and imaging capability required, the optical arrangement of the SID varies which enables them to be used in multiple setups like bright-field, fluorescence, dark-field, and multiple arrays with certain changes in their optics and illumination. This comprehensive review discusses the numerous applications and development of SIDs towards histopathological examination, detection of bacteria and viruses, food technology, and routine diagnosis. Smartphone-based devices are complemented with deep learning methods to further increase the efficiency of the devices. Graphical Abstract.

Optical design and fabrication of a smartphone fundus camera.

Fundus examination plays an important part in a medical setting. The fundus camera is one of the detection instruments used in obtaining fundus images, which can reflect information about disease and other conditions. However, traditional fundus cameras have many disadvantages in regard to data sharing, image recognition, and processing, as well as doctor-patient communication. In recent years, mobile medical systems have gradually become more prevalent in medical and health system environments. In this paper, we propose a design method for a smartphone fundus camera consisting of an illumination system and an imaging system. The end of the system can be combined with a smartphone to take the fundus images directly. We manufactured a prototype, designed an artificial eye model, and carried out a series of experiments. The results show that we can get fundus images clearly, and the imaging system will be able to correct refractive errors ranging from -8D∼+8D. The spatial resolution of the system is up to 15 µm. This is a portable device with an overall size of 160mm×160mm×80mm and a weight of 540 g. It has the advantages of lower price, simple operation, high resolution, and compact size, making it suitable as a portable ocular monitoring device.

Technical Report: A New Device Attached to a Smartphone for Objective Vision Screening.

SIGNIFICANCE: A new device attached to a smartphone was created for objective vision screening of young children including infants and newborns. The device is compact, lightweight, portable, cost-effective, and easy to operate. Therefore, it is suitable for screening large numbers of children in clinical settings, schools, and communities. PURPOSE: This article introduces a new device attached to a smartphone for objective vision screening. It can detect and categorize significant refractive errors, anisometropia, strabismus, cloudy ocular media, and ptosis that may cause amblyopia. METHODS: The new device applies the same principles as conventional streak retinoscopy but examines both eyes simultaneously and records the results electronically. The device comprises optical elements that produce a precise streak light beam and move it across a child's both eyes. The smartphone's video camera catches and records the motion of retinal reflex inside the child's pupils. By observing the direction of motion of the retinal reflex relative to the light beam motion, as well as its speed, width, and brightness, the examiner is able to assess the individual and comparative refractive status, ocular alignment, and other conditions. RESULTS: Vision screening with this device does not require any subjective response from children. The examination can be performed and analyzed by nonprofessionals after a short learning period of time. Because the examination results are electronically recorded by the smartphone, they can be stored in the child's files and sent out for professional consultations. CONCLUSIONS: The new device will provide the same functions as conventional streak retinoscopy but examines a child's both eyes simultaneously, so that, in addition to categorizing refractive errors and assessing clarity of refractive media of the eyes, it can also detect anisometropia, strabismus, and anisocoria. In addition to showing the examination results on the smartphone's screen, the device can also store the results electronically.

Do smartphone applications and activity trackers increase physical activity in adults? Systematic review, meta-analysis and metaregression.

OBJECTIVE: To determine the effectiveness of physical activity interventions involving mobile applications (apps) or trackers with automated and continuous self-monitoring and feedback. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed and seven additional databases, from 2007 to 2020. STUDY SELECTION: Randomised controlled trials in adults (18-65 years old) without chronic illness, testing a mobile app or an activity tracker, with any comparison, where the main outcome was a physical activity measure. Independent screening was conducted. DATA EXTRACTION AND SYNTHESIS: We conducted random effects meta-analysis and all effect sizes were transformed into standardised difference in means (SDM). We conducted exploratory metaregression with continuous and discrete moderators identified as statistically significant in subgroup analyses. MAIN OUTCOME MEASURES: Physical activity: daily step counts, min/week of moderate-to-vigorous physical activity, weekly days exercised, min/week of total physical activity, metabolic equivalents. RESULTS: Thirty-five studies met inclusion criteria and 28 were included in the meta-analysis (n=7454 participants, 28% women). The meta-analysis showed a small-to-moderate positive effect on physical activity measures (SDM 0.350, 95% CI 0.236 to 0.465, I2=69%, T 2=0.051) corresponding to 1850 steps per day (95% CI 1247 to 2457). Interventions including text-messaging and personalisation features were significantly more effective in subgroup analyses and metaregression. CONCLUSION: Interventions using apps or trackers seem to be effective in promoting physical activity. Longer studies are needed to assess the impact of different intervention components on long-term engagement and effectiveness.

Hybrid Ubiquitous Coaching With a Novel Combination of Mobile and Holographic Conversational Agents Targeting Adherence to Home Exercises: Four Design and Evaluation Studies.

BACKGROUND: Effective treatments for various conditions such as obesity, cardiac heart diseases, or low back pain require not only personal on-site coaching sessions by health care experts but also a significant amount of home exercises. However, nonadherence to home exercises is still a serious problem as it leads to increased costs due to prolonged treatments. OBJECTIVE: To improve adherence to home exercises, we propose, implement, and assess the novel coaching concept of hybrid ubiquitous coaching (HUC). In HUC, health care experts are complemented by a conversational agent (CA) that delivers psychoeducation and personalized motivational messages via a smartphone, as well as real-time exercise support, monitoring, and feedback in a hands-free augmented reality environment. METHODS: We applied HUC to the field of physiotherapy and conducted 4 design-and-evaluate loops with an interdisciplinary team to assess how HUC is perceived by patients and physiotherapists and whether HUC leads to treatment adherence. A first version of HUC was evaluated by 35 physiotherapy patients in a lab setting to identify patients' perceptions of HUC. In addition, 11 physiotherapists were interviewed about HUC and assessed whether the CA could help them build up a working alliance with their patients. A second version was then tested by 15 patients in a within-subject experiment to identify the ability of HUC to address adherence and to build a working alliance between the patient and the CA. Finally, a 4-week n-of-1 trial was conducted with 1 patient to show one experience with HUC in depth and thereby potentially reveal real-world benefits and challenges. RESULTS: Patients perceived HUC to be useful, easy to use, and enjoyable, preferred it to state-of-the-art approaches, and expressed their intentions to use it. Moreover, patients built a working alliance with the CA. Physiotherapists saw a relative advantage of HUC compared to current approaches but initially did not see the potential in terms of a working alliance, which changed after seeing the results of HUC in the field. Qualitative feedback from patients indicated that they enjoyed doing the exercise with an augmented reality-based CA and understood better how to do the exercise correctly with HUC. Moreover, physiotherapists highlighted that HUC would be helpful to use in the therapy process. The longitudinal field study resulted in an adherence rate of 92% (11/12 sessions; 330/360 repetitions; 33/36 sets) and a substantial increase in exercise accuracy during the 4 weeks. CONCLUSIONS: The overall positive assessments from both patients and health care experts suggest that HUC is a promising tool to be applied in various disorders with a relevant set of home exercises. Future research, however, must implement a variety of exercises and test HUC with patients suffering from different disorders.

Smartphone-Based Interventions and Internalizing Disorders in Youth: Systematic Review and Meta-analysis.

BACKGROUND: Mental health disorders in youth are a global issue that have important implications for the future quality of life and morbidity of affected individuals. In the context of public health initiatives, smartphone-based interventions have been suggested to hold the potential to be an effective strategy to reduce the symptoms of mental health disorders in youth; however, further evaluation is needed to confirm their effectiveness. This systematic review and meta-analysis documents and synthesizes existing research on smartphone-based interventions targeting internalizing disorders in youth populations. OBJECTIVE: This study aims to synthesize existing research on smartphone-based interventions targeting internalizing disorders in youth populations. METHODS: PubMed and SCOPUS were searched in 2019, and 4334 potentially relevant articles were found. A total of 12 studies were included in the final synthesis. We used the Hedges g meta-analysis approach and a random effects model for analysis. RESULTS: The results of this review note that depression and anxiety are the most commonly targeted symptoms, and unlike other similar topics, most studies reviewed were linked to a proven treatment. The overall pooled effect from the meta-analysis showed small but significant effects (κ=12; N=1370; Hedges g=0.20; 95% CI 0.02-0.38) for interventions in reducing the symptoms of internalizing disorders. In total, 4 subgroup analyses examining specific symptoms and intervention styles found varied small significant and nonsignificant effects. CONCLUSIONS: Future research should focus on developing robust evaluative frameworks and examining interventions among more diverse populations and settings. More robust research is needed before smartphone-based interventions are scaled up and used at the population level to address youth internalizing disorders.

Smartphone-enabled video-observed versus directly observed treatment for tuberculosis: a multicentre, analyst-blinded, randomised, controlled superiority trial.

BACKGROUND: Directly observed treatment (DOT) has been the standard of care for tuberculosis since the early 1990s, but it is inconvenient for patients and service providers. Video-observed therapy (VOT) has been conditionally recommended by WHO as an alternative to DOT. We tested whether levels of treatment observation were improved with VOT. METHODS: We did a multicentre, analyst-blinded, randomised controlled superiority trial in 22 clinics in England (UK). Eligible participants were patients aged at least 16 years with active pulmonary or non-pulmonary tuberculosis who were eligible for DOT according to local guidance. Exclusion criteria included patients who did not have access to charging a smartphone. We randomly assigned participants to either VOT (daily remote observation using a smartphone app) or DOT (observations done three to five times per week in the home, community, or clinic settings). Randomisation was done by the SealedEnvelope service using minimisation. DOT involved treatment observation by a health-care or lay worker, with any remaining daily doses self-administered. VOT was provided by a centralised service in London. Patients were trained to record and send videos of every dose ingested 7 days per week using a smartphone app. Trained treatment observers viewed these videos through a password-protected website. Patients were also encouraged to report adverse drug events on the videos. Smartphones and data plans were provided free of charge by study investigators. DOT or VOT observation records were completed by observers until treatment or study end. The primary outcome was completion of 80% or more scheduled treatment observations over the first 2 months following enrolment. Intention-to-treat (ITT) and restricted (including only patients completing at least 1 week of observation on allocated arm) analyses were done. Superiority was determined by a 15% difference in the proportion of patients with the primary outcome (60% vs 75%). This trial is registered with the International Standard Randomised Controlled Trials Number registry, number ISRCTN26184967. FINDINGS: Between Sept 1, 2014, and Oct 1, 2016, we randomly assigned 226 patients; 112 to VOT and 114 to DOT. Overall, 131 (58%) patients had a history of homelessness, imprisonment, drug use, alcohol problems or mental health problems. In the ITT analysis, 78 (70%) of 112 patients on VOT achieved ≥80% scheduled observations successfully completed during the first 2 months compared with 35 (31%) of 114 on DOT (adjusted odds ratio [OR] 5·48, 95% CI 3·10-9·68; p<0·0001). In the restricted analysis, 78 (77%) of 101 patients on VOT achieved the primary outcome compared with 35 (63%) of 56 on DOT (adjusted OR 2·52; 95% CI 1·17-5·54; p=0·017). Stomach pain, nausea, and vomiting were the most common adverse events reported (in 16 [14%] of 112 on VOT and nine [8%] of 114 on DOT). INTERPRETATION: VOT was a more effective approach to observation of tuberculosis treatment than DOT. VOT is likely to be preferable to DOT for many patients across a broad range of settings, providing a more acceptable, effective, and cheaper option for supervision of daily and multiple daily doses than DOT. FUNDING: National Institute for Health Research.

Wireless, battery-free and wearable device for electrically controlled drug delivery: sodium salicylate released from bilayer polypyrrole by near-field communication on smartphone.

Compared with traditional drug delivery methods, transdermal drug delivery has many advantages in avoiding the side effects in gastrointestinal tract, reducing the fluctuations in drug concentration, and improving patients' compliance. Among them, electrically controlled drug delivery is a promising solution. This work presents a wireless, battery-free and wearable device with electrically controlled drug delivery capability. The electronic component of the device is a flexible circuit board with a temperature sensor and a near-field communication module. With the help of smartphone, the device could wirelessly obtain energy and implement data transmission. The drug delivery component is a paper-based electrode modified with polypyrrole, in which non-steroidal anti-inflammatory drug sodium salicylate was encapsulated. The applied potential for electrically controlled drug delivery was more negative than -0.6 V. The drug release dose and release rates could be controlled by applying potentials with different amplitudes and durations through this device. It provided a minimalized wearable transdermal drug delivery platform for monitoring diseases such as gout. This wearable device shows promising potential in develop closed-loop drug delivery and monitoring systems for the treatment of various diseases.

(Not so) Smart sleep tracking through the phone: Findings from a polysomnography study testing the reliability of four sleep applications.

An increasing number of sleep applications are currently available and are being widely used for in-home sleep tracking. The present study assessed four smartphone applications (Sleep Cycle-Accelerometer, SCa; Sleep Cycle-Microphone, SCm; Sense, Se; Smart Alarm, SA) designed for sleep-wake detection through sound and movement sensors, by comparing their performance with polysomnography. Twenty-one healthy participants (six males, 15 females) used the four sleep applications running on iPhone (provided by the experimenter) simultaneously with portable polysomnography recording at home, while sleeping alone for two consecutive nights. Whereas all apps showed a significant correlation with polysomnography-time in bed, only SA offered significant correlations for sleep efficacy. Furthermore, SA seemed to be quite effective in reliable detection of total sleep time and also light sleep; however, it underestimated wake and partially overestimated deep sleep. None of the apps resulted capable of detecting and scoring rapid eye movement sleep. To sum up, SC (functioning through both accelerometer and microphone) and Se did not result sufficiently reliable in sleep-wake detection compared with polysomnography. SA, the only application offering the possibility of an epoch-by-epoch analysis, showed higher accuracy than the other apps in comparison with polysomnography, but it still shows some limitations, particularly regarding wake and deep sleep detection. Developing scoring algorithms specific for smartphone sleep detection and adding external sensors to record other physiological parameters may overcome the present limits of sleep tracking through smart phone apps.

Yawning while scrolling? Examining gender differences in the association between smartphone use and sleep quality.

The negative consequences of deteriorated sleep have been widely acknowledged. Therefore, research on the determinants of poor sleep is crucial. A factor potentially contributing to poor sleep is the use of a smartphone. This study aims to measure the association between overall daily smartphone use and both sleep quality and sleep duration. To this end, we exploit data on 1,889 first-year university students. Compared with previous research we control for a large set of observed confounding factors. Higher overall smartphone use is associated with lower odds of experiencing a good sleep. In addition, we explore heterogeneous differences by socioeconomic factors not yet investigated. We find that the negative association between smartphone use and sleep quality is mainly driven by female participants.

Estimation of available epinephrine dose in expired and discolored autoinjectors via quantitative smartphone imaging.

Epinephrine autoinjectors (EAIs) are important first aid medications for treating anaphylaxis. A 10-fold price increase over the past 12 years and evidence that expired EAIs may still contain significant doses of available epinephrine have motivated interest in the efficacy of expired EAIs as treatments of last resort. Degradation of expired EAIs, which can be caused by improper storage conditions, results in various degrees of discoloration of the epinephrine solution. Previous studies have determined that significant epinephrine remains available in expired EAIs, but these have only considered EAIs that show no discoloration. Here, we investigate the potential for colorimetric estimation of available epinephrine dose based on the degree of discoloration in expired EAIs. The correlation of available epinephrine dose and time since expiration date was poor (r = - 0.37), as determined by an industry standard UHPLC protocol. Visible absorbance of the samples integrated across the range 430-475 nm correlated well with available epinephrine dose (r = - 0.71). This wavelength corresponds to the blue channel of a typical smartphone camera Bayer filter. Smartphone camera images of the EAI solutions in various illumination conditions were analyzed to assign color indices representing the degree of discoloration. Color index of the samples showed similar correlation (|r| > 0.7) with available epinephrine dose as that of visible spectrophotometry. Smartphone imaging colorimetry is proposed as a potential point-of-use epinephrine dose estimator for expired and degraded EAIs. Graphical abstract.

Smartphone colorimetric determination of hydrogen peroxide in real samples based on B, N, and S co-doped carbon dots probe.

In this paper, we report the use of a smartphone and B, N, and S co-doped carbon dots (BNS-CDs) as a promising peroxidase mimic to quantify hydrogen peroxide (H2O2). The synthesized BNS-CDs exhibited excellent peroxidase-like activity to catalyze the reaction of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) with H2O2 to generate a blue oxide product (ox-TMB) with maximum absorption at 652 nm. Steady-state kinetic analysis demonstrated that the BNS-CDs showed much higher affinity than natural horseradish peroxidase (HRP) for H2O2 due to their small size and larger specific surface area. A smartphone colorimetric readout device was employed to record the RGB (red green blue) value of the ox-TMB solution via the Android application Color Grab for quantitative detection. A good linear relationship (R2 = 0.9970) between the H2O2 concentration and |R-Rblank| value was obtained in the range of 3-30 µM with a limit of detection (LOD) of 0.8 µM. The current method was successfully applied to determine H2O2 in mouthwash and milk with recoveries of 92.70-108.30%. The developed assay is a promising portable detection platform for H2O2 with good sensitivity and selectivity, simple operation, fast response, and low cost. Graphical abstract.

Accommodative Behavior, Hyperopic Defocus, and Retinal Image Quality in Children Viewing Electronic Displays.

SIGNIFICANCE: The prevalence of myopia and use of electronic displays by children has grown rapidly in recent years. We found that children viewing electronic displays, however, experience hyperopic defocus levels similar to those previously reported for other stimuli. PURPOSE: This study aimed to compare accommodative behavior of nonmyopic and myopic children viewing a computer screen or mobile phone. METHODS: Accommodative behavior was examined in 11 nonmyopic and 8 myopic children (11.32 ± 2.90 and 14.13 ± 2.30 years, respectively; P = .04; refractions, +0.51 ± 0.51 and -2.54 ± 1.29, respectively) using an open-field autorefractor (Grand Seiko) at target vergences from -0.25 to -5.00 D. Different size (scaled or nonscaled) and type (text or movie) stimuli were presented on an LCD monitor (distant) or an iPhone (near), with subjects viewing monocularly or binocularly in an illuminated or dark room. RESULTS: At the typical reading distances (20 and 33 cm), all 19 children exhibited some amount of accommodative lag. Stimulus type had little impact on accommodation. However, slightly but statistically significant lower slopes were observed (Bonferroni-corrected significance level of P ≤ .01) for low room lighting (0.96 vs. 0.91; t test, t = 3.88; P = .003), nonscaled targets (0.99 vs. 0.92; t test, t = 4.28; P = .001), and monocular viewing (0.99 vs. 0.90; t test, t = 4.0; P = .002) in the nonmyopic group only. When viewing nonscaled stimuli binocularly (natural viewing), the means and standard deviations of accommodative lags (averaged across room lights on and off, and text and movie) were generally larger for the nonmyopes at all distances and were largest at 33 cm (0.73 ± 0.18 D for the nonmyopes and 0.49 ± 0.23 for the myopes; t test, t = 2.62; P = .01). CONCLUSIONS: Generally small (≤0.50 D) amounts of hyperopic defocus are present in children binocularly viewing handheld electronic devices (nonmyopes slightly more than myopes). Modern electronic devices do not expose children to unusually high levels of hyperopic defocus.

Temporal Associations between Sleep and Daytime Functioning in Parkinson's Disease: A Smartphone-Based Ecological Momentary Assessment.

OBJECTIVES/BACKGROUND: Disruptions to mood, cognition, and other daytime functioning are common and debilitating symptoms of Parkinson's disease (PD), and there is evidence that sleep problems contribute to these symptoms. However, previous studies are limited by reliance on self-reported sleep and cross-sectional designs. With the aim of assessing sleep as a possible treatment target for improving daytime functioning in PD, we used smartphone-based ecological momentary assessment (EMA) and actigraphy to investigate temporal associations between sleep (objective and subjective) and daytime functioning. PARTICIPANTS/METHODS: Twenty participants with mild-moderate PD wore actigraphs and completed sleep diaries for 14-15 days. They reported daytime functioning (anxiety, positive affect, cognitive function, fatigue, and social function) twice daily via smartphone-administered questionnaires. Multilevel modeling examined whether sleep quantity/quality predicted next-day functioning, and whether current mood (anxiety, positive affect) predicted later sleep. RESULTS: Average completion rates for sleep diaries and daytime questionnaires were 94% and 91%, respectively. Subjective sleep quality predicted next-day anxiety (B = -.75, SE = .25, p= .003), but objective sleep did not predict any daytime functioning variables (p's>.112). Positive affect predicted later subjective sleep quality (B = 0.03, SE = .01, p = .003) but not objective sleep quantity/quality (p's>.107). CONCLUSIONS: We demonstrated the feasibility of using EMA in PD. On a daily timescale, subjective sleep quality was bidirectionally associated with mood, whereas objective sleep was not associated with any daytime functioning. This discrepancy suggests that perception of sleep is important for mood in PD, which could provide targets for non-pharmacological interventions.

Smartphone Overuse and Visual Impairment in Children and Young Adults: Systematic Review and Meta-Analysis.

BACKGROUND: Smartphone overuse has been cited as a potentially modifiable risk factor that can result in visual impairment. However, reported associations between smartphone overuse and visual impairment have been inconsistent. OBJECTIVE: The aim of this systematic review was to determine the association between smartphone overuse and visual impairment, including myopia, blurred vision, and poor vision, in children and young adults. METHODS: We conducted a systematic search in the Cochrane Library, PubMed, EMBASE, Web of Science Core Collection, and ScienceDirect databases since the beginning of the databases up to June 2020. Fourteen eligible studies (10 cross-sectional studies and 4 controlled trials) were identified, which included a total of 27,110 subjects with a mean age ranging from 9.5 to 26.0 years. We used a random-effects model for meta-analysis of the 10 cross-sectional studies (26,962 subjects) and a fixed-effects model for meta-analysis of the 4 controlled trials (148 subjects) to combine odds ratios (ORs) and effect sizes (ES). The I2 statistic was used to assess heterogeneity. RESULTS: A pooled OR of 1.05 (95% CI 0.98-1.13, P=.16) was obtained from the cross-sectional studies, suggesting that smartphone overuse is not significantly associated with myopia, poor vision, or blurred vision; however, these visual impairments together were more apparent in children (OR 1.06, 95% CI 0.99-1.14, P=.09) than in young adults (OR 0.91, 95% CI 0.57-1.46,P=.71). For the 4 controlled trials, the smartphone overuse groups showed worse visual function scores compared with the reduced-use groups. The pooled ES was 0.76 (95% CI 0.53-0.99), which was statistically significant (P<.001). CONCLUSIONS: Longer smartphone use may increase the likelihood of ocular symptoms, including myopia, asthenopia, and ocular surface disease, especially in children. Thus, regulating use time and restricting the prolonged use of smartphones may prevent ocular and visual symptoms. Further research on the patterns of use, with longer follow up on the longitudinal associations, will help to inform detailed guidelines and recommendations for smartphone use in children and young adults.

Influences on the Uptake of and Engagement With Health and Well-Being Smartphone Apps: Systematic Review.

BACKGROUND: The public health impact of health and well-being digital interventions is dependent upon sufficient real-world uptake and engagement. Uptake is currently largely dependent on popularity indicators (eg, ranking and user ratings on app stores), which may not correspond with effectiveness, and rapid disengagement is common. Therefore, there is an urgent need to identify factors that influence uptake and engagement with health and well-being apps to inform new approaches that promote the effective use of such tools. OBJECTIVE: This review aimed to understand what is known about influences on the uptake of and engagement with health and well-being smartphone apps among adults. METHODS: We conducted a systematic review of quantitative, qualitative, and mixed methods studies. Studies conducted on adults were included if they focused on health and well-being smartphone apps reporting on uptake and engagement behavior. Studies identified through a systematic search in Medical Literature Analysis and Retrieval System Online, or MEDLARS Online (MEDLINE), EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsychINFO, Scopus, Cochrane library databases, DataBase systems and Logic Programming (DBLP), and Association for Computing Machinery (ACM) Digital library were screened, with a proportion screened independently by 2 authors. Data synthesis and interpretation were undertaken using a deductive iterative process. External validity checking was undertaken by an independent researcher. A narrative synthesis of the findings was structured around the components of the capability, opportunity, motivation, behavior change model and the theoretical domains framework (TDF). RESULTS: Of the 7640 identified studies, 41 were included in the review. Factors related to uptake (U), engagement (E), or both (B) were identified. Under capability, the main factors identified were app literacy skills (B), app awareness (U), available user guidance (B), health information (E), statistical information on progress (E), well-designed reminders (E), features to reduce cognitive load (E), and self-monitoring features (E). Availability at low cost (U), positive tone, and personalization (E) were identified as physical opportunity factors, whereas recommendations for health and well-being apps (U), embedded health professional support (E), and social networking (E) possibilities were social opportunity factors. Finally, the motivation factors included positive feedback (E), available rewards (E), goal setting (E), and the perceived utility of the app (E). CONCLUSIONS: Across a wide range of populations and behaviors, 26 factors relating to capability, opportunity, and motivation appear to influence the uptake of and engagement with health and well-being smartphone apps. Our recommendations may help app developers, health app portal developers, and policy makers in the optimization of health and well-being apps.