Carbon monoxide exposures in New York City following Hurricane Sandy in 2012

Trends in carbon monoxide poisoning deaths in high frequency hurricane states from 2014-19: the need for prevention intervention strategies

INTRODUCTION

Hurricanes often result in power outages, which increase generator usage and carbon monoxide (CO) deaths. We aim to identify states with the highest frequency of hurricanes and evaluate the number of unintentional CO poisoning deaths by region, age, race and metropolitan distribution.

METHODS

The number of hurricanes was determined using the FEMA database, and the number of unintentional CO poisoning deaths was determined using the CDC WONDER database from 2014-19. Hurricane-associated consumer outages were obtained from the Department of Energy.

RESULTS

The number of unintentional CO poisoning deaths was as follows: Florida, South Carolina, North Carolina, Georgia and Alabama. Adults displayed a significantly higher number of unintentional CO poisoning deaths than pediatrics (P < 0.001). The total number of unintentional CO poisoning deaths was highest in the White population (P < 0.001); however, unintentional CO poisoning death rates were nearly two times higher among Black population in adults (0.5 versus 0.3) and pediatrics (0.2 versus 0.1). Medium metropolitan areas exhibited significantly more unintentional CO poisoning deaths (P < 0.001).

CONCLUSIONS

Hurricanes and unintentional CO poisoning deaths were most common in Florida. Death rates were higher among Black individuals. Medium metropolitan areas displayed significantly more unintentional CO poisoning deaths than all other areas.

Where are People Dying in Disasters, and Where is it Being Studied? A Mapping Review of Scientific Articles on Tropical Cyclone Mortality in English and Chinese

Background:

Tropical cyclones are a recurrent, lethal hazard. Climate change, demographic, and development trends contribute to increasing hazards and vulnerability. This mapping review of articles on tropical cyclone mortality assesses geographic publication patterns, research gaps, and priorities for investigation to inform evidence-based risk reduction.

Methods:

A mapping review of published scientific articles on tropical cyclone-related mortality indexed in PubMed and EMBASE (English) and SINOMED and CNKI (Chinese), focusing on research approach, location, and storm information, was conducted. Results were compared with data on historical tropical cyclone disasters.

Findings:

A total of 150 articles were included, 116 in English and 34 in Chinese. Nine cyclones accounted for 61% of specific event analyses. The United States (US) reported 0.76% of fatalities but was studied in 51% of articles, 96% in English and four percent in Chinese. Asian nations reported 90.4% of fatalities but were studied in 39% of articles, 50% in English and 50% in Chinese. Within the US, New York, New Jersey, and Pennsylvania experienced 4.59% of US tropical cyclones but were studied in 24% of US articles. Of the 12 articles where data were collected beyond six months from impact, 11 focused on storms in the US. Climate change was mentioned in eight percent of article abstracts.

Interpretation:

Regions that have historically experienced high mortality from tropical cyclones have not been studied as extensively as some regions with lower mortality impacts. Long-term mortality and the implications of climate change have not been extensively studied nor discussed in most settings. Research in highly impacted settings should be prioritized.

Powerless in the Virgin Islands: Emergency Department and Wound Care Clinic Utilization Following the 2017 Hurricanes Irma and Maria on St. Thomas, U.S. Virgin Islands

OBJECTIVE

The main objective of this work was to characterize the prevalence of acute medical needs by examining emergency department (ED) and outpatient wound care clinic (WCC) visits before, during, and after the 2017 Hurricanes Irma and Maria, in St. Thomas, United States (U.S.) Virgin Islands.

METHODS

Descriptive statistics and logistic regression were used to assess associations between the occurrence of the storms and visits due to injuries and chronic conditions presented to the ED and WCC from September 1, 2016 to May 31, 2018.

RESULTS

ED visits increased and the rate of injury care was higher during the storms (12 patient visits per day) than before or after the storms (9 patient visits per day). WCC visits increased during (12%) and after the storms (45%), and were associated with patients 60 years and older. The odds of ED and WCC visits due to injury during the storms were significantly higher (odds ratio [OR]: 1.28, 95% confidence interval [CI]: 1.17, 1.40) than prior to the storms. The odds for visits due to injuries were 1.19 (95% CI: 1.12, 1.28) times higher after the storms.

CONCLUSIONS

Increases occurred in ED and WCC visits for injury care during the storms and in WCC visits after the storms. Public health preparedness mandates understanding how major hurricanes impact the prevalence of acute medical needs, and the factors that influence decisions to seek medical care, in their wake.

Tropical Cyclone Exposures and Risks of Emergency Medicare Hospital Admission for Cardiorespiratory Diseases in 175 Urban United States Counties, 1999-2010

BACKGROUND

Although injuries experienced during hurricanes and other tropical cyclones have been relatively well-characterized through traditional surveillance, less is known about tropical cyclones' impacts on noninjury morbidity, which can be triggered through pathways that include psychosocial stress or interruption in medical treatment.

METHODS

We investigated daily emergency Medicare hospitalizations (1999-2010) in 180 US counties, drawing on an existing cohort of high-population counties. We classified counties as exposed to tropical cyclones when storm-associated peak sustained winds were ≥21 m/s at the county center; secondary analyses considered other wind thresholds and hazards. We matched storm-exposed days to unexposed days by county and seasonality. We estimated change in tropical cyclone-associated hospitalizations over a storm period from 2 days before to 7 days after the storm's closest approach, compared to unexposed days, using generalized linear mixed-effect models.

RESULTS

For 1999-2010, 175 study counties had at least one tropical cyclone exposure. Cardiovascular hospitalizations decreased on the storm day, then increased following the storm, while respiratory hospitalizations were elevated throughout the storm period. Over the 10-day storm period, cardiovascular hospitalizations increased 3% (95% confidence interval = 2%, 5%) and respiratory hospitalizations increased 16% (95% confidence interval = 13%, 20%) compared to matched unexposed periods. Relative risks varied across tropical cyclone exposures, with strongest association for the most restrictive wind-based exposure metric.

CONCLUSIONS

In this study, tropical cyclone exposures were associated with a short-term increase in cardiorespiratory hospitalization risk among the elderly, based on a multi-year/multi-site investigation of US Medicare beneficiaries ≥65 years.

Environmental health effects attributed to toxic and infectious agents following hurricanes, cyclones, flash floods and major hydrometeorological events

Extreme hydrometeorological events such as hurricanes and cyclones are increasing in frequency and intensity due to climate change and often associated with flash floods in coastal, urbanized and industrial areas. Preparedness and response measures need to concentrate on toxicological and infectious hazards, the potential impact on environmental health, and threat to human lives. The recognition of the danger of flood water after hurricanes is critical. Effective health management needs to consider the likelihood and specific risks of toxic agents present in waters contaminated by chemical spills, bio-toxins, waste, sewage, and water-borne pathogens. Despite significant progress in the ability to rapidly detect and test water for a wide range of chemicals and pathogens, there has been a lack of implementation to adapt toxicity measurements in the context of flash and hurricane-induced flooding. The aim of this review was to highlight the need to collect and analyze data on toxicity of flood waters to understand the risks and prepare vulnerable communities and first responders. It is proposed that new and routinely used technologies be employed during disaster response to rapidly assess toxicity and infectious disease threats, and subsequently take necessary remedial actions.

Development and Evaluation of a Theory-Based Approach to Reducing Carbon Monoxide (CO) Morbidity and Mortality: The CO Blitz Model

Carbon monoxide (CO) poisoning is preventable yet remains the most common cause of U.S. non-drug poisoning. The purpose of this non-experimental study was to develop and evaluate the theory-based CO Blitz Model. Events targeted five SC communities; volunteers provided education while local firefighters installed CO alarms. At the 4-6-month follow-up evaluation, all homes still had a functioning CO alarm; most recipients could name CO sources in their homes (78%) and what to do if the alarm sounded (90%). The theory-driven process evaluation revealed the CO Blitz Model was tailorable and effective in addressing unique community resources and needs.

Power Outage Preparedness and Concern among Vulnerable New York City Residents

Power outages can impact health, and certain populations may be more at risk. Personal preparedness may reduce impacts, but information on power outage preparedness and risk perception among vulnerable populations is limited. We examined power outage preparedness and concern among New York City residents, including vulnerable populations defined as older adults (≥ 65 years), and respondents with household members who require assistance with daily activities or depend on electric medical devices. A random sample telephone survey was conducted during November-December 2016. Preparedness was defined as having a three-day supply of drinking water, non-perishable food, and a working flashlight. Among all respondents (n = 887), 58% were prepared and 46% expressed concern about health. Respondents with electric-dependent household members (9% of all respondents) tended to have higher preparedness (70 vs. 56% of respondents without electric-dependent household members). Among this group, only 40% reported being registered with a utility company to receive early notification of outages. While the subgroup sample was small, respondents with registered electric-dependent household members had lower preparedness than those with non-registered users (59 vs. 76%). Respondents with household members who needed assistance had comparable levels of preparedness to respondents without someone who needed assistance (59 vs. 57%). Older adults had greater preparedness than younger adults (65 vs. 56%). Health concerns were greater among all vulnerable groups than the general population. Levels of preparedness varied among vulnerable respondents, and awareness of power outage notification programs was low. Our findings highlight the need to increase awareness and preparedness among at-risk people.

Health Impacts of Citywide and Localized Power Outages in New York City

BACKGROUND

Previous studies investigated potential health effects of large-scale power outages, including the massive power failure that affected the northeastern United States and Ontario, Canada, in August 2003, and outages associated with major storms. However, information on localized outages is limited.

OBJECTIVE

The study sought to examine potential health impacts of citywide and localized outages in New York City (NYC).

METHODS

Along with the citywide 2003 outage, localized outages in July 1999 and July 2006 were identified. We additionally investigated localized, warm- and cold-weather outages that occurred in any of 66 NYC electric-grid networks during 2002–2014 using New York State Public Service Commission data. Mortality and hospitalizations were geocoded and linked to the networks. Associations were estimated using Poisson time-series regression, including examining distributed lags and adjusting for temperature and temporal trends. Network-specific estimates were pooled by season.

RESULTS

Respiratory disease hospitalizations were associated with the 2006 localized outage [cumulative relative risk [CRR] over 0–1 lag day, lag₀₁=2.26 (95% confidence interval [CI]: 1.08, 4.74)] and the 2003 citywide outage, but not with other localized, warm-weather outages. Renal disease hospitalizations were associated with the 2003 citywide outage, and with localized, warm-weather outages, pooled across networks [RR at lag₃=1.16 (95% CI: 1.00, 1.34)], but not the 2006 localized outage. All-cause mortality was positively associated with the 1999, 2003, and 2006 outages (significant for the 2003 outage only), but not with other localized, warm-weather outages. Localized, cold-weather outages were associated with all-cause mortality [lag₀₁ CRR=1.06 (95% CI: 1.01, 1.12)] and cardiovascular disease hospitalizations [lag₀₁ CRR=1.14 (95% CI: 1.03, 1.26)], and fewer respiratory disease hospitalizations [lag₀₃ CRR=0.77 (95% CI: 0.61, 0.97)].

CONCLUSIONS

Localized outages may affect health. This information can inform preparedness efforts and underscores the public health importance of ensuring electric grid resiliency to climate change. https://doi.org/10.1289/EHP2154.

EMS Dispatches during Hurricanes Irene and Sandy in New Jersey

BACKGROUND

Hurricanes Irene and Sandy heavily impacted New Jersey. Investigating EMS dispatch trends during these storms may allow us to prepare for future disasters.

OBJECTIVES

Our objectives to characterize the types of EMS dispatches immediately before, during, and after landfall compared to a control period.

METHODS

This retrospective study was conducted at a large EMS dispatch center that provides first responders, Basic Life Support (BLS), Advanced Life Support (ALS), and critical care transport services to an area with approximately 20 receiving hospitals including a Level I Trauma Center. At peak staffing, there are 8-10 ALS vehicles, 25 BLS vehicles, and 3 critical care transport vehicles deployed. We included of the day of landfall and seven days before and after. We compared dispatch data to a control period in 2010 that mirrored Hurricane Sandy the dates of. Descriptive statistics and two way ANOVA were used to assess dispatch, gender and age differences.

RESULTS

We found Hurricane Sandy dispatches peaked 2 days after landfall. Both ALS and BLS had an increase in age in the post-Sandy period compared to the pre-Sandy (ALS 58.5 to 64.2, p = 0.005, ANOVA p = 0.078; BLS 47.4 to 56.3, p < 0.001, ANOVA p = 0.001). There were 17 "hurricane related" (loss of power related issues, oxygen supply depleted, evacuation) and 15 carbon monoxide dispatches in the post-Sandy period and none in the others, including peri-Irene. The average age of cardiac arrest dispatches was lower in the post-Irene group compared to pre-Irene (74.3 to 47.8, p = 0.023). There were no critical care requests before or after Hurricane Sandy, but there were 14 around Hurricane Irene and 10 surrounding the control period.

CONCLUSIONS

Dispatch data can inform natural disaster planning. Education efforts can focus on geriatric patients, as well as resource distribution planning for an increase in geriatric populations. However, pattern variability between storms shows further study is needed to clarify exactly which resources should be utilized in order to maintain an ideal response to a natural disaster.

Indoor Air Quality

Many health care providers are concerned with the role environmental exposures play in the development of respiratory disease. While most individuals understand that outdoor air quality is important to their health status, many are unaware of the detrimental effects indoor air pollution can potentially have on them. The Environmental Protection Agency (EPA) regulates both outdoor and indoor air quality. According to the EPA, indoor levels of pollutants may be up to 100 times higher than outdoor pollutant levels and have been ranked among the top 5 environmental risks to the public. There has been a strong correlation between air quality and health, which is why it is crucial to obtain a complete environmental exposure history from a patient. This article focuses on the effects indoor air quality has on the respiratory system. Specifically, this article will address secondhand smoke, radon, carbon monoxide, nitrogen dioxide, formaldehyde, house cleaning agents, indoor mold, animal dander, and dust mites. These are common agents that may lead to hazardous exposures among individuals living in the United States. It is important for health care providers to be educated on the potential risks of indoor air pollution and the effects it may have on patient outcomes. Health problems resulting from poor indoor air quality are not easily recognized and may affect a patient's health years after the onset of exposure.

No Calm After the Storm: A Systematic Review of Human Health Following Flood and Storm Disasters

Introduction How the burden of disease varies during different phases after floods and after storms is essential in order to guide a medical response, but it has not been well-described. The objective of this review was to elucidate the health problems following flood and storm disasters.

METHODS

A literature search of the databases Medline (US National Library of Medicine, National Institutes of Health; Bethesda, Maryland USA); Cinahl (EBSCO Information Services; Ipswich, Massachusetts USA); Global Health (EBSCO Information Services; Ipswich, Massachusetts USA); Web of Science Core Collection (Thomson Reuters; New York, New York USA); Embase (Elsevier; Amsterdam, Netherlands); and PubMed (National Center for Biotechnology Information, National Institutes of Health; Bethesda, Maryland USA) was conducted in June 2015 for English-language research articles on morbidity or mortality and flood or storm disasters. Articles on mental health, interventions, and rescue or health care workers were excluded. Data were extracted from articles that met the eligibility criteria and analyzed by narrative synthesis.

RESULTS

The review included 113 studies. Poisonings, wounds, gastrointestinal infections, and skin or soft tissue infections all increased after storms. Gastrointestinal infections were more frequent after floods. Leptospirosis and diabetes-related complications increased after both. The majority of changes occurred within four weeks of floods or storms.

CONCLUSION

Health changes differently after floods and after storms. There is a lack of data on the health effects of floods alone, long-term changes in health, and the strength of the association between disasters and health problems. This review highlights areas of consideration for medical response and the need for high-quality, systematic research in this area. Saulnier DD , Brolin Ribacke K , von Schreeb J . No calm after the storm: a systematic review of human health following flood and storm disasters. Prehosp Disaster Med. 2017;32(5):568-579.

Assessing health impacts of the December 2013 Ice storm in Ontario, Canada

Background

Ice, or freezing rain storms have the potential to affect human health and disrupt normal functioning of a community. The purpose of this study was to assess acute health impacts of an ice storm that occurred in December 2013 in Toronto, Ontario, Canada.

Methods

Data on emergency department visits were obtained from the National Ambulatory Care Reporting System. Rates of visits in Toronto during the storm period (December 21, 2013 – January 1, 2014) were compared to rates occurring on the same dates in the previous five years (historical comparison) and compared to those in a major unaffected city, Ottawa, Ontario (geographic comparison). Overall visits and rates for three categories of interest (cardiac conditions, environmental causes and injuries) were assessed. Rate ratios were calculated using Poisson regression with population counts as an offset. Absolute counts of carbon monoxide poisoning were compared descriptively in a sub-analysis.

Results

During the 2013 storm period, there were 34 549 visits to EDs in Toronto (12.46 per 1000 population) compared with 10 794 visits in Ottawa (11.55 per 1000 population). When considering year and geography separately, rates of several types of ED visits were higher in the storm year than in previous years in both Toronto and Ottawa. Considering year and geography together, rates in the storm year were higher for overall ED visits (RR: 1.10, 95 % CI: 1.09-1.11) and for visits due to environmental causes (RR: 2.52, 95 % CI: 2.21-2.87) compared to previous years regardless of city. For injuries, visit rates were higher in the storm year in both Toronto and Ottawa, but the increase in Toronto was significantly greater than the increase in Ottawa, indicating a significant interaction between geography and year (RR: 1.23, 95 % CI: 1.16-1.30).

Conclusions

This suggests that the main health impact of the 2013 Ice Storm was an increase in ED visits for injuries, while other increases could have been due to severe weather across Ontario at that time. This study is one of the first to use a population-level database and regression modeling of emergency visit codes to identify acute impacts resulting from ice storms.

Success Factors of European Syndromic Surveillance Systems: A Worked Example of Applying Qualitative Comparative Analysis

INTRODUCTION

Syndromic surveillance aims at augmenting traditional public health surveillance with timely information. To gain a head start, it mainly analyses existing data such as from web searches or patient records. Despite the setup of many syndromic surveillance systems, there is still much doubt about the benefit of the approach. There are diverse interactions between performance indicators such as timeliness and various system characteristics. This makes the performance assessment of syndromic surveillance systems a complex endeavour. We assessed if the comparison of several syndromic surveillance systems through Qualitative Comparative Analysis helps to evaluate performance and identify key success factors.

MATERIALS AND METHODS

We compiled case-based, mixed data on performance and characteristics of 19 syndromic surveillance systems in Europe from scientific and grey literature and from site visits. We identified success factors by applying crisp-set Qualitative Comparative Analysis. We focused on two main areas of syndromic surveillance application: seasonal influenza surveillance and situational awareness during different types of potentially health threatening events.

RESULTS

We found that syndromic surveillance systems might detect the onset or peak of seasonal influenza earlier if they analyse non-clinical data sources. Timely situational awareness during different types of events is supported by an automated syndromic surveillance system capable of analysing multiple syndromes. To our surprise, the analysis of multiple data sources was no key success factor for situational awareness.

CONCLUSIONS

We suggest to consider these key success factors when designing or further developing syndromic surveillance systems. Qualitative Comparative Analysis helped interpreting complex, mixed data on small-N cases and resulted in concrete and practically relevant findings.

Development and Application of Syndromic Surveillance for Severe Weather Events Following Hurricane Sandy

OBJECTIVE

Following Hurricane Superstorm Sandy, the New Jersey Department of Health (NJDOH) developed indicators to enhance syndromic surveillance for extreme weather events in EpiCenter, an online system that collects and analyzes real-time chief complaint emergency department (ED) data and classifies each visit by indicator or syndrome.

METHODS

These severe weather indicators were finalized by using 2 steps: (1) key word inclusion by review of chief complaints from cases where diagnostic codes met selection criteria and (2) key word exclusion by evaluating cases with key words of interest that lacked selected diagnostic codes.

RESULTS

Graphs compared 1-month, 3-month, and 1-year periods of 8 Hurricane Sandy-related severe weather event indicators against the same period in the following year. Spikes in overall ED visits were observed immediately after the hurricane for carbon monoxide (CO) poisoning, the 3 disrupted outpatient medical care indicators, asthma, and methadone-related substance use. Zip code level scan statistics indicated clusters of CO poisoning and increased medicine refill needs during the 2 weeks after Hurricane Sandy. CO poisoning clusters were identified in areas with power outages of 4 days or longer.

CONCLUSIONS

This endeavor gave the NJDOH a clearer picture of the effects of Hurricane Sandy and yielded valuable state preparation information to monitor the effects of future severe weather events. (Disaster Med Public Health Preparedness. 2016;10:463-471).

Injury Deaths Related to Hurricane Sandy, New York City, 2012

OBJECTIVE

This project aimed to describe demographic patterns and circumstances surrounding injury deaths in New York City (NYC) related to Hurricane Sandy.

METHODS

Injury deaths related to Hurricane Sandy were classified by using data from multiple sources: NYC's Office of Vital Statistics death records, Office of Chief Medical Examiner case investigation files, and American Red Cross disaster mortality data. Injury deaths were classified as being related to Hurricane Sandy if they were caused directly by the storm's environmental forces or if they were indirectly caused by an interruption of services, displacement, or other lifestyle disruption.

RESULTS

We identified 52 injury deaths in NYC related to Hurricane Sandy. Most decedents were male (75%); nearly half were aged 65 years and older (48%). Most (77%) deaths were caused by injuries directly related to Hurricane Sandy. Ninety percent of direct deaths were caused by drowning; most (73%) occurred within 3 days of landfall. Half (50%) of the 12 indirect deaths that occurred up to 30 days after the storm were caused by a fall. Nearly two-thirds (63%) were injured at home. Three-quarters (75%) of fatal injuries occurred in evacuation Zone A.

CONCLUSIONS

Risk communication should focus on older adults, males, and those living in evacuation zones; more evacuation assistance is necessary. NYC's fatal injury profile can inform future coastal storm planning efforts. (Disaster Med Public Health Preparedness. 2016;10:378-385).

Effect of Hurricane Sandy on Long Island Emergency Departments Visits

OBJECTIVE

This study aimed to examine the effect of Hurricane Sandy on Long Island mental health emergency department (ED) visits and to determine whether these visits varied according to patient demographics or geographic area and intensity of the impact.

METHODS

Individual-level de-identified data were extracted from the Statewide Planning and Research Cooperative System from New York State ED visits from October 1 to December 2012 for residents of Nassau and Suffolk counties in Long Island. The dates of the ED visits were grouped into 4 periods: (1) pre-Sandy, October 1-28; (2) during Sandy, October 29; (3) post-Sandy I, October 30 to November 1; and (4) post-Sandy II, November 2-30.

RESULTS

A total of 126,337 ED visits were recorded among 23 EDs. A significant drop in volume was observed on October 29; 399 more ED visits for physical health diagnoses were identified in the post-Sandy I period than in the pre-Sandy period. "Diseases of the respiratory system" was the only diagnosis group that showed a positive trend in the post-Sandy I period compared with the pre-Sandy period (increase of 4%). No significant changes in mental health visits were observed after Sandy landfall.

CONCLUSIONS

This analysis suggests that the critical temporal window during which ED resources should be increased is in the immediate aftermath of a hurricane. (Disaster Med Public Health Preparedness. 2016;10:344-350).

Impact of Mandatory Carbon Monoxide Alarms: An Investigation of the Effects on Detection and Poisoning Rates in New York City

OBJECTIVES

We sought to evaluate the impact of New York City's (NYC's) 2004 carbon monoxide (CO) alarm legislation on CO incident detection and poisoning rates.

METHODS

We compared CO poisoning deaths, hospitalizations, exposures reported to Poison Control, and fire department investigations, before and after the law for 2000 to 2010. Use of CO alarms was assessed in the 2009 NYC Community Health Survey.

RESULTS

Investigations that found indoor CO levels greater than 9 parts per million increased nearly 7-fold after the law (P < .001). There were nonsignificant decreases in unintentional, nonfire-related CO poisoning hospitalization rates (P = .114) and death rates (P = .216). After we controlled for ambient temperature, the law's effect on hospitalizations remained nonsignificantly protective (incidence rate ratio = 0.747; 95% confidence interval = 0.520, 1.074). By 2009, 83% of NYC residents reported having CO alarms; only 54% also recently tested or replaced their batteries.

CONCLUSIONS

Mandating CO alarms significantly increased the detection of potentially hazardous CO levels in NYC homes. Small numbers and detection bias might have limited the discovery of significant decreases in poisoning outcomes. Investigation of individual poisoning circumstances since the law might elucidate remaining gaps in awareness and proper use of CO alarms.

Utility of a near real-time emergency department syndromic surveillance system to track injuries in New York City

Background

The New York City emergency department (ED) syndromic surveillance (SS) system provides near real-time data on the majority of ED visits. The utility of ED SS for injury surveillance has not been thoroughly evaluated. We created injury syndromes based on ED chief complaint information and evaluated their utility compared to administrative billing data.

Methods

Six injury syndromes were developed: traffic-related injuries to pedal cyclists, pedestrians, and motor vehicle occupants; fall-related injuries; firearm-related injuries; and assault-related stabbings. Daily injury counts were compared for ED SS and the administrative billing data for years 2008–2010. We examined characteristics of injury trends and patterns between the two systems, calculating descriptive statistics for temporal patterns and Pearson correlation coefficients (r) for temporal trends. We also calculated proportions of demographic and geospatial patterns for both systems.

Results

Although daily volume of the injuries varied between the two systems, the temporal patterns were similar (all r values for daily volume exceeded 0.65). Comparisons of injuries by time of day, day of week, and quarter of year demonstrated high agreement between the two systems—the majority had an absolute percentage point difference of 2.0 or less. Distributions of injury by sex and age group also aligned well. Distribution of injury by neighborhood of residence showed mixed results—some neighborhood comparisons showed a high level of agreement between systems, while others were less successful.

Conclusions

As evidenced by the strong positive correlation coefficients and the small absolute percentage point differences in our comparisons, we conclude that ED SS captures temporal trends and patterns of injury-related ED visits effectively. The system could be used to identify changes in injury patterns, allowing for situational awareness during emergencies, timely response, and public messaging.

Electronic supplementary material

The online version of this article (doi:10.1186/s40621-015-0044-5) contains supplementary material, which is available to authorized users.