Measuring the Masses: Mass-Gathering Medical Case Reporting, Conceptual Modeling - The DREAM Model (Paper 5).

INTRODUCTION: Without a robust evidence base to support recommendations for first aid, health, and medical services at mass gatherings (MGs), levels of care will continue to vary. Streamlining and standardizing post-event reporting for MG medical services could improve inter-event comparability, and prospectively influence event safety and planning through the application of a research template, thereby supporting and promoting growth of the evidence base and the operational safety of this discipline. Understanding the relationships between categories of variables is key. The present paper is focused on theory building, providing an evolving conceptual model, laying the groundwork for exploring the relationships between categories of variables pertaining the health outcomes of MGs. METHODS: A content analysis of 54 published post-event medical case reports, including a comparison of the features of published data models for MG health outcomes. FINDINGS: A layered model of essential conceptual components for post-event medical reporting is presented as the Data Reporting, Evaluation, & Analysis for Mass-Gathering Medicine (DREAM) model. This model is relational and embeds data domains, organized operationally, into "inputs," "modifiers," "actuals," and "outputs" and organized temporally into pre-, during, post-event, and reporting phases. DISCUSSION: Situating the DREAM model in relation to existing models for data collection vis a vis health outcomes, the authors provide a detailed discussion on similarities and points of difference. CONCLUSION: Currently, data collection and analysis related to understanding health outcomes arising from MGs is not informed by robust conceptual models. This paper is part of a series of nested papers focused on the future state of post-event medical reporting.

Measuring the Masses: A Proposed Template for Post-Event Medical Reporting (Paper 4).

BACKGROUND: Standardizing and systematizing the reporting of health outcomes from mass gatherings (MGs) will improve the quality of data being reported. Setting minimum standards for case reporting is an important strategy for improving data quality. This paper is one of a series of papers focused on understanding the current state, and shaping the future state, of post-event case reporting. METHODS: Multiple data sources were used in creating a lean, yet comprehensive list of essential reporting fields, including a: (1) literature synthesis drawn from analysis of 54 post-event case reports; (2) comparison of existing data models for MGs; (3) qualitative analysis of gaps in current case reports; and (4) set of data domains developed based on the preceding sources. FINDINGS: Existing literature fails to consistently report variables that may be essential for not only describing the health outcomes of a given event, but also for explaining those outcomes. In the context of current and future state reporting, 25 essential variables were identified. The essential variables were organized according to four domains, including: (i) Event Domain; (ii) Hazard and Risk Domain; (iii) Capacity Domain; and (iv) Clinical Domain. DISCUSSION: The authors propose a first-generation template for post-event medical reporting. This template standardizes the reporting of 25 essential variables. An accompanying data dictionary provides background and standardization for each of the essential variables. Of note, this template is lean and will develop over time, with input from the international MG community. In the future, additional groups of variables may be helpful as "overlays," depending on the event category and type. CONCLUSIONS: This paper presents a template for post-event medical reporting. It is hoped that consistent reporting of essential variables will improve both data collection and the ability to make comparisons between events so that the science underpinning MG health can continue to advance.

Measuring the Masses: The Current State of Mass-Gathering Medical Case Reporting (Paper 1).

INTRODUCTION: Case reports are commonly used to report the health outcomes of mass gatherings (MGs), and many published reports of MGs demonstrate substantial heterogeneity of included descriptors. As such, it is challenging to perform rigorous comparisons of health services and outcomes between similar and dissimilar events. The degree of variation in published reports has not yet been investigated. OBJECTIVE: Examine patterns of post-event medical reporting in the existing literature and identify inconsistencies in reporting. METHODS: A systematic review of case reports was conducted. Included were English studies, published between January 2009 and December 2018, in Prehospital and Disaster Medicine (PDM) or Current Sports Medicine Reports (CSMR). Analysis of each paper was used to develop a list of 27 categories of data. RESULTS: Seventy-five studies were initially reviewed with 54 publications meeting the inclusion criteria. Forty-two were full case reports (78%) and 12 were conference proceedings (22%). Of the 27 categories of data studied, only 13 were consistently reported in more than 50% of publications. Reporting patterns included inconsistent use of terminology/language and variable retrievability of reports. Reporting on event descriptors, hazard and risk analysis, and clinical outcomes were also inconsistent. DISCUSSION: Case reports are essential tools for researchers and event team members such as medical directors and event producers. The authors found that current case reports, in addition to being inconsistent in content, were generally descriptive rather than explanatory; that is, focused on describing the outcomes as opposed to exploring possible connections between context and health outcomes. CONCLUSION: This paper quantifies and demonstrates the current state of heterogeneity in MG event reporting. This heterogeneity is a significant impediment to the functional use of published reports to further the science of MG planning and to improve health outcomes. Future work based on the insights gained from this analysis will aim to align and standardize reporting to improve the quality and value of event reporting.

Measuring the Masses: Domains Driving Data Collection and Analysis for the Health Outcomes of Mass Gatherings (Paper 3).

INTRODUCTION: Without a robust evidence base to support recommendations for medical services at mass gatherings (MGs), levels of care will continue to vary and preventable morbidity and mortality will exist. Accordingly, researchers and clinicians publish case reports and case series to capture and explain some of the health interventions, health outcomes, and host community impacts of MGs. Streamlining and standardizing post-event reporting for MG medical services and associated health outcomes could improve inter-event comparability, thereby supporting and promoting growth of the evidence base for this discipline. The present paper is focused on theory building, proposing a set of domains for data that may support increasingly comprehensive, yet lean, reporting on the health outcomes of MGs. This paper is paired with another presenting a proposal for a post-event reporting template. METHODS: The conceptual categories of data presented are based on a textual analysis of 54 published post-event medical case reports and a comparison of the features of published data models for MG health outcomes. FINDINGS: A comparison of existing data models illustrates that none of the models are explicitly informed by a conceptual lens. Based on an analysis of the literature reviewed, four data domains emerged. These included: (i) the Event Domain, (ii) the Hazard and Risk Domain, (iii) the Capacity Domain, and (iv) the Clinical Domain. These domains mapped to 16 sub-domains. DISCUSSION: Data modelling for the health outcomes related to MGs is currently in its infancy. The proposed illustration is a set of operationally relevant data domains that apply equally to small, medium, and large-sized events. Further development of these domains could move the MG community forward and shift post-event health outcomes reporting in the direction of increasing consistency and comprehensiveness. CONCLUSION: Currently, data collection and analysis related to understanding health outcomes arising from MGs is not informed by robust conceptual models. This paper is part of a series of nested papers focused on the future state of post-event medical reporting.

Psychosocial Influences on Patient Presentations: Considerations for Research and Evaluation at Mass-Gathering Events.

AIM: This review discusses the need for consistency in mass-gathering research and evaluation from a psychosocial perspective. BACKGROUND: Mass gatherings occur frequently throughout the world. Having an understanding of the complexities of mass gatherings is important to determine required health resources. Factors within the environmental, psychosocial, and biomedical domains influence the usage of health services at mass gatherings. A standardized approach to data collection is important to identify a consistent reporting standard for the psychosocial domain. METHOD: This research used an integrative literature review design. Manuscripts were collected using keyword searches from databases and journal content pages from 2003 through 2018. Data were analyzed and categorized using the existing minimum data set as a framework. RESULTS: In total, 31 manuscripts met the inclusion criteria. The main variables identified were use of alcohol or drugs, crowd behavior, crowd mood, rationale, and length of stay. CONCLUSION: Upon interrogating the literature, the authors have determined that the variables fall under the categories of alcohol or drugs; maladaptive and adaptive behaviors; crowd behavior, crowd culture, and crowd mood; reason for attending event (motivation); duration; and crowd demographics. In collecting psychosocial data from mass gatherings, an agreed-upon set of variables that can be used to collect de-identified psychosocial variables for the purpose of making comparisons across societies for mass-gathering events (MGEs) would be invaluable to researchers and event clinicians.

Environmental Influences on Patient Presentations: Considerations for Research and Evaluation at Mass-Gathering Events.

AIM: This paper discusses the need for consistency in mass-gathering research and evaluation from an environmental reporting perspective. BACKGROUND: Mass gatherings occur frequently throughout the world. Having an understanding of the complexities of mass gatherings is important to inform health services about the possible required health resources. Factors within the environmental, psychosocial, and biomedical domains influence the usage of health services at mass gatherings. A minimum data set (MDS) has been proposed to standardize collection of biomedical data across various mass gatherings, and there is a need for an environmental component. The environmental domain includes factors such as the nature of the event, availability of drugs or alcohol, venue characteristics, and meteorological factors. METHOD: This research used an integrative literature review design. Manuscripts were collected using keyword searches from databases and journal content pages from 2003 through 2018. Data were analyzed and categorized using the existing MDS as a framework. RESULTS: In total, 39 manuscripts were identified that met the inclusion criteria. CONCLUSION: In collecting environmental data from mass gatherings, there must be an agreed-upon MDS. A set of variables can be used to collect de-identified environmental variables for the purpose of making comparisons across societies for mass-gathering events (MGEs).

On the Way Out: An Analysis of Patient Transfers from Four Large-Scale North American Music Festivals Over Two Years.

INTRODUCTION: Music festivals are globally attended events that bring together performers and fans for a defined period of time. These festivals often have on-site medical care to help reduce the impact on local health care systems. Historically, the literature suggests that patient transfers off-site are frequently related to complications of substance use. However, there is a gap in understanding why patients are transferred to hospital when an on-site medical team, capable of providing first aid services blended with a higher level of care (HLC) team, is present. OBJECTIVE: The purpose of this study is to better understand patterns of injuries and illnesses that necessitate transfer when physician-led HLC teams are accessible on-site. METHODS: This is a prospective, descriptive case series analyzing patient encounter documentation from four large-scale, North American, multi-day music festivals. RESULTS/DISCUSSION: On-site medical teams that included HLC team members were present for the duration of each festival, so every team was able to "treat and release" when clinically appropriate. Over the course of the combined 34 event days, there were 10,406 patient encounters resulting in 156 individuals being transferred off-site for assessment, diagnostic testing, and/or treatment. A minority of patients seen were transferred off-site (1.5%). The patient presentation rate (PPR) was 16.5/1,000. The ambulance transfer rate (ATR) was 0.12/1,000 attendees, whereas the total transfer-to-hospital rate (TTHR), when factoring in non-ambulance transport, was 0.25/1,000. In contrast to existing literature on transfers from music festivals, the most common reason for transfer off-site was for musculo-skeletal (MSK) injuries (53.8%) that required imaging. CONCLUSION: The presence of on-site HLC teams impacted the case mix of patients transferred to hospital, and may reduce the number of transfers for intoxication. Confounding preconceptions, patients in the present study were transferred largely for injuries that required specialized imaging and testing that could not be performed in an out-of-hospital setting. These results suggest that a better understanding of the specific effects on-site HLC teams have on avoiding off-site transfers will aid in improving planning for music festivals. The findings also identify areas for further improvement in on-site care, such as integrated on-site radiology, which could potentially further reduce the impact of music festivals on local health services. The role of non-emergency transport vehicles (NETVs) deserves further attention.TurrisSA, CallaghanCW, RabbH, MunnMB, LundA. On the way out: an analysis of patient transfers from four large-scale North American music festivals over two yearsPrehosp Disaster Med. 2019;34(1):72-81.

Mortality at Music Festivals: An Update for 2016-2017 - Academic and Grey Literature for Case Finding.

In 2016, the authors published a paper on music festival fatalities between the years 1999 and 2014 (n=722). In this Special Report, they provide an update on fatalities reported at music festivals globally for the period 2016-2017 (n=201). Using a search strategy designed to capture grey literature and media reports of music festival fatalities, reports of the overall frequency and cause-of-death breakdown for publicly reported, festival-related deaths are recorded. This update shows an increase in the frequency of festival-related fatality reports during the new period, together with an increase in the number of deaths attributable to terror (n=60) and overdose/poisoning (n=41). Drawing conclusions about the cause of this increase is challenging given the growth in Internet use, online media reports, and number of music festivals occurring annually when compared with the previous reporting period. The authors re-emphasize the need for a uniform reporting standard and reliable epidemiological data for fatalities related to music festivals, mass gatherings, and special events. TurrisSA, JonesT, LundA. Mortality at music festivals: an update for 2016-2017 - academic and grey literature for case finding. Prehosp Disaster Med. 2018;33(5):553-557.

Nonlinear Modelling for Predicting Patient Presentation Rates for Mass Gatherings.

IntroductionMass gatherings are common in Australia. The interplay of variables, including crowd density and behavior, weather, and the consumption of alcohol and other drugs, can pose a unique set of challenges to attendees' well-being. On-site health services are available at most mass gatherings and reduce the strain on community health facilities. In order to efficiently plan and manage these services, it is important to be able to predict the number and type of presenting problems at mass gatherings.ProblemThere is a lack of reliable tools to predict patient presentations at mass gatherings. While a number of factors have been identified as having an influence on attendees' health, the exact contribution of these variables to patient load is poorly understood. Furthermore, predicting patient load at mass gatherings is an inherently nonlinear problem, due to the nonlinear relationships previously observed between patient presentations and many event characteristics. METHODS: Data were collected at 216 Australian mass gatherings and included event type, crowd demographics, and weather. Nonlinear models were constructed using regression trees. The full data set was used to construct each model and the model was then used to predict the response variable for each event. Nine-fold cross validation was used to estimate the error that may be expected when applying the model in practice. RESULTS: The mean training errors for total patient presentations were very high; however, the distribution of errors per event was highly skewed, with small errors for the majority of events and a few large errors for a small number of events with a high number of presentations. The error was five or less for 40% of events and 15 or less for 85% of events. The median error was 6.9 presentations per event. CONCLUSION: This study built on previous research by undertaking nonlinear modeling, which provides a more realistic representation of the interactions between event variables. The developed models were less useful for predicting patient presentation numbers for very large events; however, they were generally useful for more typical, smaller scale community events. Further research is required to confirm this conclusion and develop models suitable for very large international events.Arbon P, Bottema M, Zeitz K, Lund A, Turris S, Anikeeva O, Steenkamp M. Nonlinear modelling for predicting patient presentation rates for mass gatherings. Prehosp Disaster Med. 2018;33(4):362-367.

Patient Presentation Trends at 15 Mass-Gathering Events in South Australia.

IntroductionMass gatherings are complex events that present a unique set of challenges to attendees' health and well-being. There are numerous factors that influence the number and type of injuries and illnesses that occur at these events, including weather, event and venue type, and crowd demographics and behavior.ProblemWhile the impact of some factors, such as weather conditions and the availability of alcohol, on patient presentations at mass gatherings have been described previously, the influence of many other variables, including crowd demographics, crowd behavior, and event type, is poorly understood. Furthermore, a large number of studies reporting on the influence of these variables on patient presentations are based on anecdotal evidence at a single mass-gathering event. METHODS: Data were collected by trained fieldworkers at 15 mass gatherings in South Australia and included event characteristics, crowd demographics, and weather. De-identified patient records were obtained from on-site health care providers. Data analysis included the calculation of patient proportions in each variable category, as well as the total number of patient presentations per event and the patient presentation rate (PPR). RESULTS: The total number of expected attendees at the 15 mass gatherings was 303,500, of which 146 presented to on-site health care services. The majority of patient presentations occurred at events with a mean temperature between 20°C and 25°C. The PPR was more than double at events with a predominantly male crowd compared to events with a more equal sex distribution. Almost 90.0% of patient presentations occurred at events where alcohol was available. CONCLUSION: The results of the study suggest that several weather, crowd, and event variables influence the type and number of patient presentations observed at mass-gathering events. Given that the study sample size did not allow for these interactions to be quantified, further research is warranted to investigate the relationships between alcohol availability, crowd demographics, crowd mobility, venue design, and injuries and illnesses.Anikeeva O, Arbon P, Zeitz K, Bottema M, Lund A, Turris S, Steenkamp M. Patient presentation trends at 15 mass-gathering events in South Australia. Prehosp Disaster Med. 2018;33(4):368-374.

Patient Presentations and Medical Logistics at Full and Half Ironman Distance Triathlons.

We describe logistical challenges, illness/injury rates, as well as medical and ambulance transfer rates (ATR) at an annual large-scale half/full triathlon in a remote location. Prospective observational study; registry data. Data on patient presentation rates, percentage of patients transferred by ambulance, transfer to hospital rates (TTHR), ATR, and medical usage rates were collected and analyzed. In total, 1923 athletes participated in the 2016 triathlon (1404 in the full-length race and 519 in the half) and 181 patient encounters were documented. The patient presentation rate (PPR) was 94 in 1000 patients, and 1.6% of patients seen onsite required offsite medical care. TTHR and ATR were 1.6 in 1000 and 0.5 in 1000, respectively. Gastrointestinal issues were the most common presentation (50/181; 27.6%), followed by musculoskeletal injury (46/181; 25.4%) and nonspecific dizziness (37/181; 20.4%). The incorporation of a coordinated event medical plan and team, with integrated on-course and at-finish coverage, may have minimized presentations of patients to local health care services; therefore, decreasing the effect on the local ambulance service and health infrastructure of the host community.

The Event Chain of Survival in the Context of Music Festivals: A Framework for Improving Outcomes at Major Planned Events.

Despite the best efforts of event producers and on-site medical teams, there are sometimes serious illnesses, life-threatening injuries, and fatalities related to music festival attendance. Producers, clinicians, and researchers are actively seeking ways to reduce the mortality and morbidity associated with these events. After analyzing the available literature on music festival health and safety, several major themes emerged. Principally, stakeholder groups planning in isolation from one another (ie, in silos) create fragmentation, gaps, and overlap in plans for major planned events (MPEs). The authors hypothesized that one approach to minimizing this fragmentation may be to create a framework to "connect the dots," or join together the many silos of professionals responsible for safety, security, health, and emergency planning at MPEs. Adapted from the well-established literature regarding the management of cardiac arrests, both in and out of hospital, the "chain of survival" concept is applied to the disparate groups providing services that support event safety in the context of music festivals. The authors propose this framework for describing, understanding, coordinating and planning around the integration of safety, security, health, and emergency service for events. The adapted Event Chain of Survival contains six interdependent links, including: (1) event producers; (2) police and security; (3) festival health; (4) on-site medical services; (5) ambulance services; and (6) off-site medical services. The authors argue that adapting and applying this framework in the context of MPEs in general, and music festivals specifically, has the potential to break down the current disconnected approach to event safety, security, health, and emergency planning. It offers a means of shifting the focus from a purely reactive stance to a more proactive, collaborative, and integrated approach. Improving health outcomes for music festival attendees, reducing gaps in planning, promoting consistency, and improving efficiency by reducing duplication of services will ultimately require coordination and collaboration from the beginning of event production to post-event reporting. Lund A , Turris SA . The Event Chain of Survival in the context of music festivals: a framework for improving outcomes at major planned events. Prehosp Disaster Med. 2017;32(4):437-443.

Improving Data Quality in Mass-Gatherings Health Research.

Mass gatherings attract large crowds and can strain the planning and health resources of the community, city, or nation hosting an event. Mass-Gatherings Health (MGH) is an evolving niche of prehospital care rooted in emergency medicine, emergency management, public health, and disaster medicine. To explore front-line issues related to data quality in the context of mass gatherings, the authors draw on five years of management experience with an online, mass-gathering event and patient registry, as well as clinical and operational experience amassed over several decades. Here the authors propose underlying human, environmental, and logistical factors that may contribute to poor data quality at mass gatherings, and make specific recommendations for improvement through pre-event planning, on-site actions, and post-event follow-up. The advancement of MGH research will rely on addressing factors that influence data quality and developing strategies to mitigate or enhance those factors. This is an exciting time for MGH research as higher order questions are beginning to be addressed; however, quality research must start from the ground up to ensure optimal primary data capture and quality. Guy A , Prager R , Turris S , Lund A . Improving data quality in mass-gatherings health research. Prehosp Disaster Med. 2017;32(3):329-332.

Mortality at Music Festivals: Academic and Grey Literature for Case Finding.

OBJECTIVE: Deaths at music festivals are not infrequently reported in the media; however, the true mortality burden is difficult to determine as the deaths are not yet systematically documented in the academic literature. METHODS: This was a literature search for case examples using academic and gray literature sources, employing both retrospective and prospective searches of media sources from 1999-2014. RESULTS: The gray literature documents a total of 722 deaths, including traumatic (594/722; 82%) and non-traumatic (128/722; 18%) causes. Fatalities were caused by trampling (n=479), motor-vehicle-related (n=39), structural collapses (n=28), acts of terror (n=26), drowning (n=8), assaults (n=6), falls (n=5), hanging (n=2), and thermal injury (n=2). Non-traumatic deaths included overdoses (n=96/722; 13%), environmental causes (n=8/722; 1%), natural causes (n=10/722; 1%), and unknown/not reported (n=14/722; 2%). The majority of non-trauma-related deaths were related to overdose (75%). The academic literature documents trauma-related deaths (n=368) and overdose-related deaths (n=12). One hundred percent of the trauma-related deaths reported in the academic literature also were reported in the gray literature (n=368). Mortality rates cannot be reported as the total attendance at events is not known. CONCLUSIONS: The methodology presented in this manuscript confirms that deaths occur not uncommonly at music festivals, and it represents a starting point in the documentation and surveillance of mortality. Turris SA , Lund A . Mortality at music festivals: academic and grey literature for case finding. Prehosp Disaster Med. 2017;32(1):58-63.

Mass-gathering Medicine: Risks and Patient Presentations at a 2-day Electronic Dance Music Event - Year Two.

Turris SA , Camporese M , Gutman SJ , Lund A . Mass-gathering medicine: risks and patient presentations at a 2-day electronic dance music event - year two. Prehosp Disaster Med. 2016;31(6):687-688.

Exploring International Views on Key Concepts for Mass-gathering Health through a Delphi Process.

Introduction The science underpinning mass-gathering health (MGH) is developing rapidly. However, MGH terminology and concepts are not yet well defined or used consistently. These variations can complicate comparisons across settings. There is, therefore, a need to develop consensus and standardize concepts and data points to support the development of a robust MGH evidence-base for governments, event planners, responders, and researchers. This project explored the views and sought consensus of international MGH experts on previously published concepts around MGH to inform the development of a transnational minimum data set (MDS) with an accompanying data dictionary (DD). Report A two-round Delphi process was undertaken involving volunteers from the World Health Organization (WHO) Virtual Interdisciplinary Advisory Group (VIAG) on Mass Gatherings (MGs) and the MG section of the World Association for Disaster and Emergency Medicine (WADEM). The first online survey tested agreement on six key concepts: (1) using the term "MG HEALTH;" (2) purposes of the proposed MDS and DD; (3) event phases; (4) two MG population models; (5) a MGH conceptual diagram; and (6) a data matrix for organizing MGH data elements. Consensus was defined as ≥80% agreement. Round 2 presented five refined MGH principles based on Round 1 input that was analyzed using descriptive statistics and content analysis. Thirty-eight participants started Round 1 with 36 completing the survey and 24 (65% of 36) completing Round 2. Agreement was reached on: the term "MGH" (n=35/38; 92%); the stated purposes for the MDS (n=38/38; 100%); the two MG population models (n=31/36; 86% and n=30/36; 83%, respectively); and the event phases (n=34/36; 94%). Consensus was not achieved on the overall conceptual MGH diagram (n=25/37; 67%) and the proposed matrix to organize data elements (n=28/37; 77%). In Round 2, agreement was reached on all the proposed principles and revisions, except on the MGH diagram (n=18/24; 75%). Discussion/Conclusions Event health stakeholders require sound data upon which to build a robust MGH evidence-base. The move towards standardization of data points and/or reporting items of interest will strengthen the development of such an evidence-base from which governments, researchers, clinicians, and event planners could benefit. There is substantial agreement on some broad concepts underlying MGH amongst an international group of MG experts. Refinement is needed regarding an overall conceptual diagram and proposed matrix for organizing data elements. Steenkamp M , Hutton AE , Ranse JC , Lund A , Turris SA , Bowles R , Arbuthnott K , Arbon PA . Exploring international views on key concepts for mass-gathering health through a Delphi process. Prehosp Disaster Med. 2016;31(4):443-453.

Observed Benefits to On-site Medical Services during an Annual 5-day Electronic Dance Music Event with Harm Reduction Services.

BACKGROUND: With increasing attendance and media attention, large-scale electronic dance music events (EDMEs) are a subset of mass gatherings that have a unique risk profile for attendees and promoters. Shambhala Music Festival (Canada) is a multi-day event in a rural setting with a recognized history of providing harm reduction (HR) services alongside medical care. Study/Objective This manuscript describes the medical response at a multi-day electronic music festival where on-site HR interventions and dedicated medical care are delivered as parallel public health measures. METHODS: This study was a descriptive case report. Medical encounters and event-related data were documented prospectively using an established event registry database. RESULTS: In 2014, Shambhala Music Festival had 67,120 cumulative attendees over a 7-day period, with a peak daily attendance of 15,380 people. There were 1,393 patient encounters and the patient presentation rate (PPR) was 20.8 per one thousand. The majority of these (90.9%) were for non-urgent complaints. The ambulance transfer rate (ATR) was 0.194 per one thousand and 0.93% of patient encounters were transferred by ambulance. No patients required intubation and there were no fatalities. Harm reduction services included mobile outreach teams, distribution of educational materials, pill checking facilities, a dedicated women's space, and a "Sanctuary" area that provided non-medical peer support for overwhelmed guests. More than 10,000 encounters were recorded by mobile and booth-based preventive and educational services, and 2,786 pills were checked on-site with a seven percent discard rate. CONCLUSION: Dedicated medical and HR services represent two complementary public health strategies to minimize risk at a multi-day electronic music festival. The specific extent to which HR strategies reduce the need for medical care is not well understood. Incorporation of HR practices when planning on-site medical care has the potential to inform patient management, reduce presentation rates and acuity, and decrease utilization and cost for local, community-based health services.