Abstract 11560: Systematic Deployment of AEDs in BC Schools: A Utility and Cost-Effectiveness Study of In-School and Nearby OHCAs

Background: While pediatric out-of-hospital cardiac arrests (OHCAs) are relatively uncommon, they have a much higher number of potential years of life lost per event. School-located public access automated external defibrillators (AED) may be beneficial to school-aged OHCAs, but also other OHCAs within the school and in the surrounding community. We sought to identify the incidence of OHCAs within and nearby schools in British Columbia (BC), to estimate the number that may benefit from school-located AEDs. Methods: We used prospectively-collected data from the BC OHCA Registry from 2013 to 2018. We examined the addresses of all OHCAs to determine those occurring in public primary and secondary schools. We geo-plotted all OHCAs to identify the number of OHCAs within walking distance of a school. Assuming an average pedestrian speed for AED retrieval of 1.8 m/second, we calculated the number of school-vicinity OHCAs for which a bystander could retrieve an AED prior to a 6.5 minute emergency medical system response interval, assuming that AEDs would be located on the exterior of a school building. Results: There were a total of 401,423 children enrolled at 824 schools annually in the study footprint. Of a total of 12,480 EMS-treated OHCAs (220 aged < 18 years), 20 were in in schools, of which 4 were <18 years of age. Of school located OHCAs, 14 (70%) had initial shockable rhythms, 4 (20%) had an AED applied (of whom 3 survived), and 10 (50%) survived. Of the four school-located pediatric OHCAs, three were witnessed (75%), two had initial shockable rhythms (50%), and two (50%) survived until hospital discharge. A total of 1128/12,480 (9%) OHCAs were within retrieval distance of a school, corresponding to 0.228 per school per year (95% CI 0.201-0.255 year-to-year) , which is above current thresholds for cost-effectiveness. Conclusion: Outcomes of school-located OHCAs are encouraging, especially those with AED application. While the incidence of school-located OHCAs is low, a substantial proportion of OHCAs occur within a retrievable distance to a school, and thus accessible external school-located AEDs may improve overall OHCA outcomes of a community.

Capturing richer information: On establishing the validity of an interval-valued survey response mode

Obtaining quantitative survey responses that are both accurate and informative is crucial to a wide range of fields. Traditional and ubiquitous response formats such as Likert and visual analogue scales require condensation of responses into discrete or point values—but sometimes a range of options may better represent the correct answer. In this paper, we propose an efficient interval-valued response mode, whereby responses are made by marking an ellipse along a continuous scale. We discuss its potential to capture and quantify valuable information that would be lost using conventional approaches, while preserving a high degree of response efficiency. The information captured by the response interval may represent a possible response range—i.e., a conjunctive set, such as the real numbers between 3 and 6. Alternatively, it may reflect uncertainty in respect to a distinct response—i.e., a disjunctive set, such as a confidence interval. We then report a validation study, utilizing our recently introduced open-source software (DECSYS), to explore how interval-valued survey responses reflect experimental manipulations of several factors hypothesised to influence interval width, across multiple contexts. Results consistently indicate that respondents used interval widths effectively, and subjective participant feedback was also positive. We present this as initial empirical evidence for the efficacy and value of interval-valued response capture. Interestingly, our results also provide insight into respondents’ reasoning about the different aforementioned types of intervals—we replicate a tendency towards overconfidence for those representing epistemic uncertainty (i.e., disjunctive sets), but find intervals representing inherent range (i.e., conjunctive sets) to be well-calibrated.

The Association Between The Interval of Radioiodine Treatment and The Response and Adverse Effect in Patients with Non-Progressive Lung Metastases From Differentiated Thyroid Cancer

Purpose To assess the association between the interval of radioiodine treatment (RT) and short-term response and adverse effects in patients with non-progressive lung metastases from differentiated thyroid cancer (DTC).Methods A total of 147 neighboring RT course pairs from 78 patients with 131I-avid non-progressive lung metastases from DTC were retrospectively analyzed. The courses were categorized into two groups by interval of neighboring therapeutic 131-I administrations (≤12 months and >12 months). The short-term therapy response and adverse effects of the two groups were evaluated.Results No significant differences were found between the two groups in the change rate of thyroid stimulating hormone (TSH) stimulated serum thyroglobulin (ΔsTg%) (P=0.806) or the change rate of metastasis lesion long diameter (ΔLLD%) (P=0.246). In the subanalysis considering the number of treatments (3 and >3 times), no significant difference was found (P>0.05). No difference was found in biochemical response (interval ≤12m: P=0.325, interval >12m:P=0.456) or structural response (interval ≤12m: P=0.760, interval >12m: P=0.563) between the former and latter courses with regard to different intervals. No difference was found in adverse events between former and latter courses with regard to different intervals (P>0.05).Conclusions The interval of RTs is not associated with the short-term response or adverse effects in patients with non-progressive lung metastases from DTC. Appropriately prolonging the interval in specific patients seems to be feasible, and the interval of RT should be individually managed in clinical practice.

Dissemination and Refutation of Rumors During the COVID-19 Outbreak in China: Infodemiology Study

Background During the outbreak of COVID-19, numerous rumors emerged on the internet in China and caused confusion among the public. However, the characteristics of these rumors in different phases of the epidemic have not been studied in depth, and the official responses to the rumors have not been systematically evaluated. Objective The aims of this study were to evaluate the rumor epidemic and official responses during the COVID-19 outbreak in China and to provide a scientific basis for effective information communication in future public health crises. Methods Data on internet rumors related to COVID-19 were collected via the Sina Weibo Official Account to Refute Rumors between January 20 and April 8, 2020, extracted, and analyzed. The data were divided into five periods according to the key events and disease epidemic. Different classifications of rumors were described and compared over the five periods. The trends of the epidemic and the focus of the public at different stages were plotted, and correlation analysis between the number of rumors and the number of COVID-19 cases was performed. The geographic distributions of the sources and refuters of the rumors were graphed, and analyses of the most frequently appearing words in the rumors were applied to reveal hotspots of the rumors. Results A total of 1943 rumors were retrieved. The median of the response interval between publication and debunking of the rumors was 1 day (IQR 1-2). Rumors in text format accounted for the majority of the 1943 rumors (n=1241, 63.9%); chat tools, particularly WeChat (n=1386, 71.3%), were the most common platform for initial publishing of the rumors (n=1412, 72.7%). In addition to text rumors, Weibo and web pages were more likely to be platforms for rumors released in multimedia formats or in a combination of formats, respectively. Local agencies played a large role in dispelling rumors among social media platforms (1537/1943, 79.1%). There were significant differences in the formats and origins of rumors over the five periods (P<.001). Hubei Province accounted for most of the country’s confirmed rumors. Beijing and Wuhan City were the main centers for debunking of disinformation. The words most frequently included in the core messages of the rumors varied by period, indicating shifting in the public’s concern. Conclusions Chat tools, particularly WeChat, became the major sources of rumors during the COVID-19 outbreak in China, indicating a requirement to establish rumor monitoring and refuting mechanisms on these platforms. Moreover, targeted policy adjustments and timely release of official information are needed in different phases of the outbreak.

Rumor Epidemic and Responses During the Period of COVID-19 Outbreak in China (Preprint)

BACKGROUND During the outbreak period of COVID-19, numerous rumors emerged on the Internet in China causing cognitive chaos among the public. However, these rumors’ characteristics at different phases of the epidemic have not been studied in depth and the official response to rumors has also not been evaluated systematically. OBJECTIVE To evaluate rumor epidemic and official responses during COVID-19 outbreak in China, providing a scientific basis for effective information communication in future public health crises. METHODS Data on Internet rumors related to COVID-19, collected via Sina Weibo Platform to Refute Rumors between January 20 and April 8, 2020, were extracted and analyzed. Different classifications of rumors were described and compared over the 5 periods. The trend of the epidemic and the public’s focus at different stages were plotted, the geographic distribution of rumors and rumor-refuters were graphed, and content analyzes were applied to reveal the hot spot of the rumors. RESULTS A total of 1,943 rumors were retrieved. The median of the response interval between publication and debunking of rumors was 1 day. Rumors in texts accounted for the majority (63.9%); chat tools were the most common platform for their initial publishing (72.7%). Weibo and web pages were more likely to be the platforms for rumors released as combination and multimedia, respectively. Local agencies played a large role in dispelling rumors among social media platforms (79.1%). There were significant differences in the forms and origins of rumors over the 5 periods (P <0.001). Hubei Province accounted for most of the country’s confirmed rumors. Beijing and Wuhan city were the main centers for disinformation debunking. The hot words included in the headlines of rumors varied over periods, indicating shifting public’s concern. CONCLUSIONS Chat tools, particularly WeChat, had become the major origins of rumors during this outbreak, indicating the requirement to establish rumor monitoring and refuting mechanism on such platforms. Meanwhile, targeted policy adjustments and timely release of official information are needed in different phases of the outbreak.

Abstract 295: Improving Response to Out-Of-Hospital Cardiac Arrest: Verified Responder Pilot Program

Background: Survival following out-of-hospital cardiac arrest (OHCA) decreases as the interval from collapse to CPR and defibrillation increases. Most OHCA events occur in private locations. Innovative approaches are needed to reduce response interval, especially into private locations. Methods: We undertook the Verified Responder Program in 5 United States communities during calendar year 2018, whereby off-duty EMS professionals volunteered and were equipped with Philips automated external defibrillators (AEDs). Volunteers were alerted using a geospatial smartphone application (PulsePoint) integrated with 9-1-1 dispatch to respond to nearby private and public suspected OHCA. The prospective study evaluated the frequency of verified responder alert, response, scene arrival, and initial care for OHCA occurring prior to EMS arrival. The investigation surveyed responder experience using a 5 point Likert scale. OHCA surveillance was assessed using the CARES registry. Results: The Verified Responder Program involved 593 volunteers equipped with 550 AEDs drawn from 5 EMS agencies covering a population of 1.3 million persons (Table 1). Of the 660 eligible OHCA events (483 private, 177 public), verified responders were alerted in 9.4% (n=62) of events. Among the 483 in a private location, responders were alerted in 10.4% (n=50), responded in 2.1% (n=10), arrived on scene in 1.7% (n=8), and provided initial care in 1.5% (n=7). Among the 177 in a public location, responders were alerted in 6.8% (n=12), responded in 3.4% (n=6), arrived on scene in 2.8% (n=5), and provided initial care in 1.1% (n=2). Overall, responders reported a highly favorable experience (4.5/5). None reported an adverse event. Conclusions: In this initial US-based experience of smartphone alert program for suspected OHCA in private or public locations, volunteer experiences were uniformly favorable. Volunteers were alerted, responded, and involved in a small fraction of OHCA.

Abstract 228: Epidemiology and Outcome of Out-Of-Hospital Cardiac Arrests in Kunming, Yunnan, China

Objective: The purpose of this study was to better understand the epidemiological features and outcomes of emergency medical service(EMS)-assessed out-of-hospital cardiac arrests(OHCAs) in Kunming,Yunnan,China. Methods: In this prospective study,datas were collected according to the Utstein style on all cases of OHCAs from January 2010 to December 2014 in urban areas covered by Kunming EMS system.The outcomes were analysed at four time points of survival: no return of spontaneous circulation (no-ROSC),return of spontaneous circulation (ROSC),survival to hospital admission, and survival to hospital discharge.The adjusted odds ratios(ORs) and 95% confidence intervals(CIs) for survival were calculated and adjusted for potential risk factors using stratified multivariable logistic regression analysis. Results: There were 3387 EMS-assessed OHCAs with cardiac aetiology from 2010 to 2014. The incidence of EMS-assessed OHCA with cardiac aetiology was 20.7 per 100,000 inhabitants per year. Of the 3387 EMS-assessed OHCAs with cardiac aetiology,the rates of ROSC,survival to admission and survival to discharge were 12.4%,3.5% and 0.9% respectively. There were only 73(2.2%)patients with initial rhythm of ventricular fibrillation(VF) or pulseless ventricular tachycardia(VT) observed in the EMS-assessed OHCAs with cardiac aetiology.There was no statistical difference among the five years in outcomes of OHCAs with cardiac aetiology.Younger age, bystander CPR,witnessed by EMS, OHCA with initial rhythm of VF/pulseless VT,shorter medication interval,and shorter response interval were associated with a higher rate of survival to discharge respectively. Conclusion: In the urban areas of Kunming covered by EMS system, survival outcome of OHCA was unsatisfactory.Improvements are required in every link of the chain of survival.

A superb solo, or a deviant duet? Overlapping songs in superb fairy-wrens

Avian duets are formed when 2 birds coordinate their songs. Most research on the evolution and function of duetting has focused on species with highly coordinated duets, and less is known about the context and function of overlapping songs that are more loosely coordinated, in part due to the challenge of determining whether such vocalizations coincide by chance or through coordination between the partners. Here, we use field recordings and playback experiments to test whether breeding pairs of superb fairy-wrens, Malurus cyaneus, coordinate their territorial songs to form duets. We test 3 key characteristics of duetting; whether partners’ songs 1) overlap more than expected by chance; 2) have a stereotyped structure that occurs repeatedly and predictably in time, and 3) show evidence of a constant time lag between the contributions of the 2 participants, indicating that individuals are coordinating their songs. This is the first study to quantify the temporal precision of song between partners to investigate coordination in the Malurus genus, an important model taxon for song, sexual selection, and speciation. We found variation in the extent to which partners’ songs overlapped, with some individuals overlapping their partners’ songs more than expected by chance, no difference in structure of solo and overlapping songs, and no evidence of a consistent response interval. Thus song overlap in superb fairy-wrens meets only some criteria for duetting. We suggest that overlapping songs in this species may be due to individuals responding independently of the same stimulus and/or “call and answer” between pair members.