Considerations in the epidemiology of earthquake injuries

4.

Nicholas P. Jones, M.EERl, Frederick Krimgold, M.EERl, Eric K. Noji, M.EERl, andGordon S. Smith, M.EERl

In July, 1989, a workshop entitled "Earthquake Injury Epidemiology forMitigation and Response" was held at The Johns Hopkins University inBaltimore, Maryland, U.S.A. The aim of the workshop.was to gather agroup of interested professionals, all directly or peripherally interested inthe research, planning, mitigation, and response aspects associated withearthquake-induced injuries and deaths, to lay the foundations and beginto develop a research agenda for this emerging field. This was achievedby a combination of presentation of summary papers, discussions in small,multidisciplinary working groups, and plenary wrap-up and discussion sessions. The papers and transcriptions are available from the authors. Thefollowing paper presents a condensation and summary of the workshop,its discussions, and its important conclusions. References are cited whereappropriate; much of the content reflects a condensation of the discussions.

Introduction

Significant resources in research support and effort have been expended on theproblem of earthquake hazard mitigation over the past twenty years. Most of thisresearch effort has been directed toward questions of geophysical research and structural engineering. While this expenditure of effort has been appropriate in termsof advancing scientific understanding of the underlying phenomena responsible forearthquake losses, the principal threat of earthquakes is loss of human life. Materialloss is for the most part replaceable or subject to compensation. The tragic fact is

(NPJ) Dept. Civ, Engrg., The Johns Hopkins Univ., Baltimore, Md 21218-2699(FK) College Arch. & Urb. Studies, Virginia Polytech. Inst. & State Univ., Alex.,Va 22314.(EKN) Dept. Emerg. Med., The Johns Hopkins Univ., Baltimore, Md 21205(GSS) Injury Prevo Ctr., The Johns Hopkins Univ., Baltimore, Md 21205

507'1:Earthquake Spectra. Vol. 6. No.3. 1990

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Considerations in the Epidemiologyof Earthquake Injuries

508 N. P. Jones, F. Krimgold, E. K. Noji, and G. S. Smith Considerations in

that earthquakes continue to consume human beings. The specific mechanisms ofdeath and injury in earthquakes have not yet been the subject of extensive study.Early work by epidemiologists suggests, however, that efforts to reduce earthquakerelated fatality and injury may benefit from more disciplined study (1-4,8,9,11,14,15).Subsequent work by architects and engineers has pointed to the possibility of morerigorous data gathering in the aftermath of major earthquakes (12,13).

Until recently, there has been no effective or coordinated program of researchinto earthquake injury epidemiology. While there have been a few preliminary studies from individual researchers in several disciplines, this topic has suffered the fateof many trans disciplinary problems. It has been dealt with peripherally by severaldisciplines, but not accepted as the central responsibility of any particular researchgroup. The topic is difficult to approach from any narrow disciplinary background,as it requires the collaboration of several disciplines. First, it is necessary to understand the mechanisms of physical failure in earthquakes. This requires structuralengineering and architectural competence. Secondly, it is necessary to understandthe process of human injury in earthquake-induced building failure. The implicationsof building/occupant interaction are the critical issue in prevention of life loss andinjury. Understanding these medical aspects, as well as the behaviors influencing theoutcomes requires both physicians and social scientists. Thirdly, it is necessary todevelop an analytical framework for the analysis of injury patterns and the relationship between specific causative agents and their negative consequences (15-20). Theinvolvement of epidemiologists, particularly those familiar with injuries, is essential.

This epidemiological dimension has only recently begun to be explored. In a majorearthquake, such as the 1985 Mexican or 1988 Armenian events, intensive groundshaking near populated areas can result in the severe damage and even collapse ofinadequately-constructed buildings. The potential for loss of life in such a collapse ishigh, in addition to the economic loss associated with the structure and its contents.Preliminary results are now becoming available from these events. Partial resultshave been collected from Chile (1985) (20), the Southern Italian earthquake (1980)(2,3) and Tangshan (1976) (10). There is now enough data available to initiate seriousdiscussion and to raise serious methodological issues.

In response to this need, an international workshop on the epidemiology of injuriesin natural disasters, specifically earthquakes, was organized by the authors of thispaper and held at The Johns Hopkins University in Baltimore, Maryland, U.S.A. inJuly, 1989.

The basic objectives of the workshop were the following:

• To reviewThis inch;injury pat

• To definethe scopethe establ.

• To identifmade, or 1

• To identif

• To introdimunicatioing, earthand rescue

• To enhancpractition.

• To formulr

The workshcto developing th

• The worksappropriat

• The subjeinjury epicaspects?

• Presentatinecessary.

Presented blduring the discuare available (J(

[i, and G. S. Smith Considerations in the Epidemiology of Earthquake Injuries 509

: mechanisms ofextensive study.uce earthquake-4,8,9,11,14,15).ssibility of more

• To review the state of the art in the rather diversefieldof disaster epidemiology.This included reviews of data collected in past events of causes of death andinjury patterns.

• -To define the field of earthquake injury epidemiology. This included definingthe scope of the problem area, identifyingthe applications for the research, andthe establishment of a research agenda.

• To identify relevant expertise. Who are the individuals/organizations who havemade, or have the potential for making, significantcontributions in the area?

• To identify and unify relevant sourcesof data.

• To introduce the problem area to related research communities and begin communication between relevant groups, includingarchitecture, structural engineering, earthquake engineering, emergencymedicine, injury epidemiology, searchand rescue (SAR), occupant safety, and occupant behavior.

• To enhance communication between the research community and the user orpractitioner community concernedwith life safety in buildings.

Organization of the Workshop

The workshop was held over a three-day period. Careful consideration was givento developing the structure and organization of the workshopfor several reasons:

• The workshop was multidi.!ciplinary. Care was taken to ensure adequate andappropriate mixing of participants from the variousprofessionsdiscussed above.

• The subject was relatively poorly defined i.e., what, precisely, is earthquakeinjury epidemiology,and howdoes it interfacewith the mitigation and responseaspects? .

logy of injuriesLuthors of thisand, U.S.A. in

• Presentation of past research from the perspectiveof the various disciplineswasnecessary.

Presented below 15 a summary of the discussions and important points raisedduring the discussions. These are presented in summary form; detailed ·transcriptionsare available (Jones et al. 1989).

510 N. P. Jones, E Krimgold, E. K. Noji, and G. S. Smith Considerationsir

Summary of Discussions of epidemiologiused to effect crresponse. In pesignificant effec

Consider thto on-site mediate, post-hospiprocess", e.g., 'clear that the tent levels of deWhether infornblock, developr:lection method,The medical reoperation. It iserational structthese in future

The most fundamental question raised was what is the precise purpose and definition of earthquake injury epidemiology? What information is needed, for whatapplication will it be used, and can it be gathered in a quantitative, rather thanqualitative way? Can it be used to help mitigate future impacts? The associatedmethodological question is: What are the questions that need to be asked and methods used to obtain this information? Can epidemiologic methods be used to studythis problem, and the various processes involved, in such a way as to provide insightsinto the answers to some of the above questions?

The purpose of earthquake injury epidemiology is to determine the distribution ofdeath and injury in earthquakes, and in particular to consider the causal mechanismof the fatal or nonfatal injury. The causal mechanism is difficult to define precisely, asare the appropriate variables and indicators describing it. It is necessary to considerhazard exposure, construction types and their performance during earthquakes, influence of nonstructural components and building contents, occupancy and occupant

bese

interaction of several disciplines.For the above components, there are large differences from country to country;

international interaction is also needed. Standardization of terminology and methodologies must therefore transcend cultural as well as disciplinary boundaries. Whethersuch a multidisciplinary and multinational approach is feasible is open to some question.

Unfortunately, it is not clear from the relatively sketchy data that are availablefrom past earthquakes exactly where the efforts and finances should be focused. Ifit is found, for example, that most severe injuries or deaths are resulting from inappropriate responses on the part of the victims, then education should be targeted asa priority item. If a large number of people are dying because they are not beingextricated quickly enough, then extrication or rescue equipment needs improvement.If a large number of people are dying after extrication then it is necessary to improveemergency treatment procedures. Unfortunately, the above scenarios are speculative: detailed epidemiologic studies of injuries in past events have not, in general,occurred. The information required to make the type of decision exemplified aboveis not available.

The purpose of disaster epidemiology, as suggested by the workshop title andechoed repeatedly by workshop participants is mitigation and response: The results

The informnot been coUecdifficult to collefrom the rescu

lacking; there 1:restrictions oftemergency int.those who canimproved metl:

The usefuhthe methodolois often no di:hospital admisearthquake-reiof severity (4)there is a reasc

Considerations in the Epidemiology of Earthquake Injuriesand G. S. Smith 511

.rpose and defeded, for whate, rather thanThe associated.ked and rneth-used to study

'rovide insights

of epidemiologic studies of injuries in disasters, in this case earthquakes, are to beused to effect casualty reduction by improving both mitigation, or preparedness, andresponse. In particular, the behavior of victims during the impact phase may havesignificant effect on their outcomes.

Consider the medical aspect of the relief phase. This aspect can be broken downto on-site medical assistance, transportation, hospital treatment and, if appropriate, post-hospital care. At this scale, identification of a weak link in the "medicalprocess", e.g., transportation delays, can be important to enhancing survival. It isclear that the types of information needed at this stage in the process require different levels of detail, and are required by different personnel in different time frames.Whether information is needed at the level corresponding to a particular structure,block, development, town, city or country has a profound influence on the data collection methodology implemented and on the types of questions whichmust be asked.The medical response must also then be somehowaggregated into the total responseoperation. It is important to identify where problems may have occurred in this operational structure in the past, and efforts made to establish procedures to minimizethese in future events.

distribution ofsal mechanismne precisely, asary to considerlrthquakes, in. and occupantovided. Thesebut require the

Data Needs and Collection Methodology

ry to country;y and methodaries, Whetherto some ques-

The information that is needed in the immediate response phase has generallynot been collected in the past. There are a number of reasons for this: the data aredifficult to collect; time spent collecting this information is often viewed as detractingfrom the rescue effort; the exact definition of what data to collect has generally beenlacking; there has been no person with the soleresponsibility for data collection; accessrestrictions often hamper the data collection effort. The primary focus of immediateemergency intervention in the response phase is to reduce human losses: to savethose who can be saved. Unfortunately, due to the paucity of data, development ofimproved methods has been limited.

.t are availablebe focused. Ifing from inapbe targeted asare not beingimprovement.

ary to improve-s are speculaot , in general,nplified above

Data Sources from Past Events

shop title andre: The resuIts

The usefulness of past data is difficult to assess in general terms, and depends onthe methodology used and questions asked in the collection. As an example, thereis often no distinction made in the time period following an earthquake whetherhospital admissions are earthquake-related or not: they are often just assumed to beearthquake-related. Often the definition of injury is unclear and gives no indicationof severity (4). Discrimination requires a detailed follow-up study. In most cases,there is a reasonable amount of data available as regards structural performance, but

· P. Jones,F. Krimgold, E. K. oji, and G. S. Smith Considerationsin512

data on injury which are any more than anecdotal are scarce. Even fewer cases existwhere specific injury-structure interaction data are available.

The 1987WIrian Hospital apstudies have alsr

The 1988 A

techniques such as record searching or questionnaire distribution require much effort.It is considered that sufficient data exist on past events that comparative studies maynow begin to be made.

amounts of datviews, to captuidue to the extertion of the even

A number of

Other types of "disasters" may provide useful information relevant to the earthquake injury problem. For example, the Kansas City Hyatt skywalk collapse, theBridgeport L'Ambience Plaza collapse, tornado, hurricane, fire, terrorist bombing,and mine-related collapses all potentially present mass casualty situations. Whilethe specific details of the collapse or mechanisms of injury may vary, parallels mayprovide insight.

As an example of the possible use of past earthquakes as sources of data, somediscussion at the workshop focused on the significant effort that has been made recently to compile data from the 1906 San Francisco earthquake, using newspaperaccounts, letters, coroner's records and U.S. Army archives (6). Building informationis also available. While incomplete, it may be possible to generate some structuralperformance-morbidity /mortality correlations. Data are likely to exist on the Veteran's Administration hospital collapse in the 1971 San Fernando earthquake withthe L.A. Fire Department or the V.A. itself. The Ministry of Health in San Salvador has some information on the Ruben Dario collapse, and some injury-structurestudies were performe~. The Romanian earthquake (1976) is considered a source ofbehavioral and structural data as related to injuries.

Someopportunities appear to remain from the 1985Mexicoearthquake. A databaseon the organizational aspects exists at the Disaster Research Center at the University of Delaware. Injury data is apparently available at the Juarez Hospital and theGeneral Hospital, and there is some structural data available also. Surprisingly, theengineering data available on collapsed structures in Mexico is rather scarce, as thesebuildings were cleared away as soon as possible after the earthquake.

quakes were meof quantitative:for the Peruviaof questionablemay also be avt

General SOt

records, and .tlOfficeof U.S. Fand other disasthese sources c:

While evenexisting data sclimitations of t

It was clea;mechanism of i

It is importare identified,scope of dataquestions askecrepetitive data

The typesthe data into E

1. Earthqu;location

i, and G. S. Smith 513Considerationsin the EpidemiologyofEarthquakeInjuries

ewer cases exist The 1987 Whittier Narrows earthquake is a possiblesource for data. The Presbyterian Hospital apparently has information on 250-300 people injured. Somebehavioralstudies have also been done, and structural information is sure to be available.

The 1988 Armenian event presents a rather unique possibility to collect largeamounts of data. Projects are currently underway, making particular use of interviews, to capture as much information as possible. It has been speculated, however,due to the extent of the catastrophe, that many records were lost, making reconstruction of the event difficult.

A number of other potential sourceswerediscussed. "Ancient" or historical earthquakes were mentioned. It is unlikely that such events would yield much in the wayof quantitative injury-structure data, or even injury data. Selected data are availablefor the Peruvian and Chilean earthquakes related to injuries, but the latter may beof questionable validity. Archival data on Italian, Iranian and Japanese earthquakesmay also be available, but again the data are considered poor.

General sources of information were mentioned such as hospital and doctor'srecords, and the journals and archives of historical and geological societies. TheOffice of U.S. Foreign Disaster Assistancemaintains a database on past earthquakesand other disasters, but not in a detailed form. While not all necessarily complete,these sources can serve to provide as complete a picture as possible of past events.

While even the above list is incomplete, it was deemed important to investigateexisting data sources for as much useful information as possible, keeping in mind thelimitations of the data, and inherent uncertainties and lack of reliability.

.s, and assist inlabor intensive:ire much effort.ive studies may

affecting urbanenvironments isfrom the Glass. (5) to planning

:1tto the earthlk collapse, therorist bombing,uations. Whiler, parallels may

s of data, some: been made re

sing newspapering informationsome structural:ist on the Vetarthquake withlth in San Salinjury-structureered a source of

Identification of Critical Variables

lake. A database. at the Univer

.ospital and theiurprisingly, thescarce, as these

It was clear that a better database of statistical information relating injuries tomechanism of injury is required.

It is important that the appropriate variables or indicators, and their interactionsare identified, in the generation of a multivariate model of outcome. The type andscope of data required must be defined based on the focus of the study, and thequestions asked must reflect what weknowalready, to avoid collection ofunnecessarilyrepetitive data and improve the level of detail and quality.

The types of data to be collected will vary, as stated. It is convenient to groupthe data into several categories, and give examples:

Earthquake Information such as time of day, magnitude and local intensity, andlocation of epicenter relative to site of interest.


2. Demographic Data reflecting spatial variations in population density, urban/ruraldistinctions, the economic and cultural characteristics of the region, etc.

5. S.ARJnformation such as method and time of extrication, arrival time of SARequipment, effectiveness of SAR response both technically and operationally.

for classifying t.comprehensive ssets of question:facilitated.

The questiorpline and organetc.) The consitional dimensiozational level a:country.

What questinformation nee

The timing.five phases of d

3. Building Characteristics such as construction type, materials, occupancy, "strength"on an appropriate scale, collapse or damage characteristics, nonstructural element performance, evidence of fire, and so on.

4. Me<ll!=MTreatment _Chcy:acteristi~including nature and severity of injury, treatment received, cause of death, times of discovery, extrication and hospitalization, hospital treatment received, final outcome. etc. It is also essential tocollect detailed data on the precise mechanism of injury. In addition, specialized data may be needed, e.g., to evaluate the incidence of earthquake-inducedheart attacks in victims.

6. Behavioral Factors including occupant behavior before, during and after theimpact, reaction to warnings, etc. are important influences in determininginjury severity or death.

1. Retrosper

may influcurrent" dhealth cal

The above list is by no means comprehensive. Coupled with the identification ofthe variables or indicators is the methodology used to collect them. Methodologicalissues are discussed in detail in the following section. This includes consideration ofthe perishability of the data, the sources of the data, and the means used to recordthem.

2. Data colleffectiven

Data Collection Methodology

3. Impact pBecause·this pote.this phas

4. Response

as the orin the recollectiorhealth ai

injury de

5. Follow-uplete the

The souretand ultimate,

Perhaps one of the most important issues discussed at the workshop was thepreparedness aspect as it relates to data collection, and methodological issues. Specifically, the definition and organization of the questions to be asked, when to ask them,of whom, and by whom all need to be addressed before the fact. The following recommendations and observations were made with regard to data collection methods.

It is clear from past events that the existence of a defined set of focused yetcomprehensive questions is critical. To effectively improve preparedness and responsecapability at all levels, the "right" questions must be asked, and in a timely manner.The questions must serve to test particular hypotheses. and address operationalissues. Each discipline should develop its own questions, perhaps using appropriatequantitative scales such as the injury severity score (14) and a corresponding scale

i, and G. S.Smith

rsity, urban/rural.gion, etc.

:cupancy, "strength"mstructural ele-

y of injury, treatand hospitalizaalso essential toddition, special;hquake-induced

val time of SARoperationally.

19 and after thein determining

identification of~ethodologicalconsideration ofs used to record

rrkshop was thecal issues. Specifhen to ask them,he following recection methods.t of focused yetess and responseL timely manner..ress operationalsing appropriateresponding scale

Considerationsin the EpidemiologyofEarthquakeInjuries 515

for classifying the collapsed state of a structure, and then incorporate these into acomprehensive survey instrument. If consensuscan be reached on these questions, orsets of questions, comparative studies of the effects of different earthquakes will befacilitated.

The questions should fit into a hierarchical model, with dimensions of time, discipline and organizational level (e.g., on-site, local hospital, public health department,etc.) The consideration of a four-dimensional matrix was suggested, with the additional dimension of function, although in some cases, this may overlap the organizationallevel axis. It should be noted that the organizational structure varies withcountry.

What questions are to be asked is a function of time. It is apparent that theinformation needs vary dramatically from one phase to the next.

The timing of data collection may be divided into five phases, connected to thefive phases of disaster, all of which are important in the overall process:

1. Retrospective collection from past events, to whatever extent possible, whichmay influence preparedness and planning activities. In addition, collection ofcurrent data, as regards assessments (e.g., structural), preparedness (e.g., ofhealth care system, SAR capability), etc. would be carried out in this phase.

2. Data collection in the pre-disaster phase, as related to response to warnings,effectiveness of preparedness plans, etc.

3. Impact phase: In most cases this is the most critical yet difficult data to obtain.Because of the initial chaotic state, it is generally extremely difficult to collectthis potentially most perishable data. Raw video footage is of potential use inthis phase.

4. Response phase collection is similar to the impact phase in many cases, althoughas the organized response begins to take over, collection is possible if includedin the response plan. Collaboration with local teams may be important in thiscollection phase. During this time it is essential to make contact with localhealth authorities to ensure that collection of appropriate hospital and otherinjury data is possible.

5. Follow-up, detailed data collection, using interviews and questionnaires, to complete the process begun in 3 and 4. above.

The source of the information in many cases will determine the level of detailand ultimate application of the data. For example, in the impact or response phases,

516 N, p, Jones,F. KrimgoJd, E. K,Noji, and G. S. Smith Considerationsin th,

with regard to emergency medical response, questions asked concerning "needs" willcertainly obtain different responses if health departments, hospital administrators,individual physicians and rescue or EMT's are asked. Each group has its own viewand assessment of the situation.

The priorities for data collection must be established a priori. In the impact andresponse phases, for example, data collection personnel must not be burdened withrequirements to collect what may be termed archival information: records, reportsor data which are not immediately available, at the expense of perishable data whichmay be available only in the context of the impact phase, or data which are criticalin terms of mobilization of response. The definition of data as perishable or archivaldepends crucially on the application, and such identification must be made in advance.

Development of data-collection instruments for the impact and response phasesmust reflect the difficult situation which exists at such times. Questionnaires or formsshould allow for the collection of detailed and anecdotal information as it is available.Terminology must be standardized across disciplines. Computers were suggested aspotentially useful.

Development of a trial form for use in future incidents was considered a highpriority. This could be circulated for review by each of the disciplines involved, andtested in future events. A strategy for deployment of the form must also be developed.

It was considered extremely important that response teams include personnelwhose function is to collect data. Assessment teams, appropriately deployed, shouldbe responsible for gathering not only data which will be used in long-term analysisand research tasks, but also "intelligence" information which can be used to guideSAR and medical personnel. Recorders of data and their sources must be identified.The multidisciplinary nature of the data required must be captured in the collectioninstrument, yet reflect the fact that the collector will most likely not be an expertin more than one or two areas. Composition of assessment teams should reflect thisdifficulty.

Tracking victims through the response system was considered an important consideration. In this way, outcomes can be related to circumstances of injury, on-sitetreatment, extrication, transportation, and hospital treatment, and the timing ofeach.

Carefully designed, comprehensive follow-up, sample surveys of building occupants should be conducted. Data should be collected on all occupants of damagedstructures, whether injured or not, and case studies conducted where possible. Dataon the uninjured is potentially of great use in understanding interaction of occupants

with building danThe National

routinely conductquite different frobe of use for guid

Data collectiO!being there to thand even betweention processes, arprepared to releato the media, arcan result in lOSEbefore organizedby untrained, locfected populatiorin preparing date'

An importantconnaissance tee.collection methoctivities.

Loss estimat.preparedness ac:casualties. One (epidemiologic sttdeveloped or ref

Exactly whacarefully definedlacerations, contso-called to distrDoes the model

At the natioinjured. This inand for responsto the planning

Ioji, and G. S.Smith

·ning "needs" will11 administrators,has its own view

.n the impact andbe burdened with: records, reportsshable data whichwhich are criticalshable or archivalmade in advance.r response phasesonnaires or forms. as it is available.vere suggested as

onsidered a highnes involved, andilso be developed.nclude personneldeployed, should-ng-term analysisbe used to guideust be identified.in the collection

lot be an experthould reflect this

1important conof injury, on-siterd the timing of

-f building occuants of damaged'e possible. Data.ionof occupants


with building damage.The National Transportation Safety Board (N.T.S.B), and other organizations

routinely conduct post-disaster investigations. While in most cases the situations arequite different from earthquake disasters, protocols have been developed which maybe of use for guiding procedures in the latter event.

Data collection is not always simply a matter of having the questions defined, andbeing there to the collect the data. Political problems, internationally, nationally,and even between organizational or responding departments can often hinder collection processes, and restrict information flow. In many cases, sources are simply notprepared to release, or allow access to, critical data. Researchers, or perceived linksto the media, are often particularly suspect. Damage to facilities, e.g., hospitals,can result in loss of information. How can data be collected in the critical hoursbefore organized rescue teams arrive, when a large numbers of rescues are performedby untrained, local volunteers. The psychologicaland emotional responses of an affected population (e.g., those who are in mourning or shock) need to be consideredin preparing data collection methodologies, particularly interviews.

An important purpose of data collectionis that of guiding response. Rapid reconnaissance techniques, facilitated through the development of appropriate datacollection methodologies, are necessary to guide impact and response-phase SAR activities.

Casualty Estimation Modeling

Loss estimation models are frequently used by planners and public officials inpreparedness activities. "Loss" may refer to property and economic losses, or tocasualties. One of the potential uses for the data collected through earthquake injuryepidemiologic studies is as a database with which casualty estimation models may bedeveloped or refined. Much discussion at the workshop addressed this issue.

Exactly what a casualty estimation model is designed to accomplish must becarefully defined. Are estimates of the breakdown of injuries given, e.g., orthopedic,lacerations, contusions, etc.? Does the model predict final outcomes, or the initial orso-called to distribution of deaths and injury or injury severity before intervention?Does the model produce aggregate information. or structure-specific informat.ion?

At the national level it is important to make reliable estimates of the dead andinjured. This includes, for preparedness and planning purposes, pre-event estimates,and for response, impact or response-phase estimates, which represent refinementsto the planning model based on reconnaissance. The latter are necessary for the

N. P. Jones, F. KrimgoJd,E. K. Noji, and G. S. Smith Considerations in the518

allocation of resources after the event (28). At the local level, models predicting theSAR demand for particular structures are essential for effective responses.

Is it even possible to develop general models which are based on individual eventsor individual structures or blocks of structures? While this is a difficult task, theconsensus was that this is necessary. In addition to providing a rational method forcasualty estimation, which is essential to planners, such models enable the mechanismof injury in earthquakes to be elucidated through identification and observation ofcritical variables, and also provide a framework for data collection in future events(32,33). While the development of comprehensive models was generally consideredimportant, there were questions raised as to the possibility of achieving a "universalmodel."

One of the important features of such a model is the potential for identifying howthe variables interact and how independent risk factors modulate the expected outcomes. Sensitivity of the model to small changes in the variables should be addressed.Spatial models would greatly assist in resource allocation planning both before andafter an event.

The interactive relationship between modeling and data collection was stressed.Proposed critical indicators, which become collected data (deductive), can be evaluated through the framework of a model (inductive), and revised, accepted or rejectedthrough retrospective application.

There are some serious doubts as to the validity of existing casualty estimationmodels - both pre-event and post-event. While they often have been instrumentalin motivating preparedness activities, their reliability, and thereby usefulness for detailed planning are generally limited. Most are based on engineering models with littleinput from medicine or epidemiology. It is common for post-event damage estimates,and therefore casualty estimates to initially err on the low side. This is perhaps a faultwhich lies with the organization and implementation of rapid post-event reconnaissance. The problem is a difficult one: both the Mexico and Lorna Prieta earthquakesexhibited localized areas of intense damage interspersed throughout large, relativelyunaffected areas.

The development of probabilistic models is seen as an important need in this area.Not only should expected numbers of casualties be given, but also the variances ofthe estimates, and the associated statistical moments for the various variables andindicators in the model. In this way, estimates can be improved (i.e., the variance ofthe estimate reduced) as more data become available. Pre-event predictions can bemodified quickly after the event by performing reconnaissance activities.

The usefulness·assessment and resunlikely that detailor hazardous mate

Intervention strFor example, whatrapid and effectivesurvival of a very f

The abili ty tobut this capabilityof hazardous [potemitigation activiti-

Effective chan,component of earas related to injurlack of a coherentis scarce, particulrinjury is assumedcharacterization isto the causal mec!

A number of ifactors on casualtinitial usable voltpotential. It is a t

throughout the stof building collapboth occupants 0:

Are there descollapse and provsome structures ashould the structsuggested, but itfor protection of

The effect of ;is important, anc

Noji, and G. S. Smith

dels predicting theesponses.

n individual eventsdifficult task, the

ational method forrble the mechanismand observation ofan in future eventsenerally consideredieving a "universal

ror identifying howthe expected out

.ould be addressed.Ig both before and

:tion was stressed.ive), can be evalu:cepted or rejected

asualty estimationbeen instrumental. usefulness for de; models with littledamage estimates,5 is perhaps a fault.t-event reconnais:>rietaearthquakesut large, relatively

t need in this area.o the variances ofious variables ande., the variance oforedictions can be


The usefulness of models for SAR operations remains to be proven. While initialassessment and resource allocation issues can be impacted by reliable models, it isunlikely that detailed, on-site peculiarities are addressable (e.g., the presence of fireor hazardous material risks) without first-hand information.

Intervention strategies will affect outcomes, and models need to address this issue.For example, what impact will SAR processes have in improving outcomes? Can arapid and effective response system significantly reduce casualties or only affect thesurvival of a very small proportion of all casualties.

Engineering Issues

The ability to make assessments about collapse potential of buildings is limited,but this capability is important for pre-event estimation procedures. Identificationof hazardous (potentially lethal) buildings in the anticipatory phase is important formitigation activities. There have been some attempts to study collapse mechanics .

is scarce, particularly quantitatively. The relationship between building damage andinjury is assumed in a general sense, not established statistically or otherwise. Thischaracterization is needed to both enable correlation of the type and severity of injuryto the causal mechanism and to assist in the triage, as described above.

A number of indicators were proposed as indicators for the effect of structuralfactors on casualty. Volume change, the ratio of the loss in usable volume to theinitial usable volume is suggested as a measure of void potential, hence survivalpotential. It is a single-parameter estimate, however, and provides no differentiationthroughout the structure, and has other limitations. Scales for quantifying "degreesof building collapse" are needed. Separation of walls may have significant effects onboth occupants or nearby pedestrians; this is difficult to quantify, in the usual sense.

Are there design techniques that can be used which address the possibility ofcollapse and provide for "safe" regions or voids in the collapsed structure? In Texas,some structures are designed with a concrete core to afford protection from tornadoesshould the structure otherwise fail. In a similar vein, designing to provide voids wassuggested, but it is unlikely that clients would want to address such issues. Designingfor protection of escape routes may be more acceptable.

The effect of nonstructural components and building contents on occupant injury.is important, and needs further study.


Structural characteristics also relate to behavioral factors. For example, folk wis-.dom claims such things as: "run outside" or "do not run outside" or "wait threeminutes then run outside;" "stand under a door frame;" and so on. The correctaction depends on the particular structure. Detailed study should provide the basisfor valid education to avoid incorrect actions being taken by occupants. Incorrectextrapolations are often made.

Development and testing of new SAR equipment is an engineering issue. Testingand evaluation of equipment is necessary to determine what is the best to use invarious applications. Most existing equipment has been adapted from other uses, andis not particularly well-suited to the collapsed building environment. For example,determination of victim status after detection is important in terms of operationaldecisions New specialized technologies potentially will suffer from the fact that theywill generally not be mass-produced products, and there will be reluctance to pursuedevelopment in industry. Studies and development of SAR equipment should bepursued in a focused and coordinated manner.

and water leaks:impact phase.

One issue raiother factors inbuilding should :

While much,noted that orgasponse. For exawhich follows aneeds to be stu:body of researchboth with regarresearch in eartJ

Some discusBehavioral Issues injuries" and "«

earthquakes. (failures, e.g., reclassifications 0or at least defin

While it was"requiring mediit was noted thunreliable. Toseverity is impnoted that botlpersonnel needneeds to be deshould be madeand those treatof severity avai

Assessmentbacktracking irconcept of tractality, and detintervention st

Behavioral aspects must be considered to produce effective casualty estimationmodels or for SAR operational guidelines.

The basic behavioral questions are: What was an occupant doing when the earthquake occurred, what was his or her initial response and what did he or she do afterthe earthquake? Why were these actions taken? Did they represent a learned response? Were factors like culture or age a factor? What behavior is appropriate?What is inappropriate? Can public education programs provide valuable advice thatpeople will use in the impact phase? Clearly, answers to these questions must be obtained from post-event interviews in most cases; data collection methodologies whichinvolve interviews should try to address these questions in addition to those relatingto structure and injury. It was noted that past studies on occupant behavior do exist, such as the Imperial County Services Building during the 1979 Imperial Valleyearthquake (20).

o epjCLe.mjology

occupant survival.that a more site-specific approach is needed. The question was raised, however,whether prior training does actually effectively change behavior under stress. Moreresearch needs to be done in this area, and in the development of more effectiveteaching tools. It is likely that it is easier to teach behaviors such as checking for gas

J'oji,and G. S. Smith

.xample, folk wis

e" or "wait threeon. The correctprovide the basisipants. Incorrect

ing issue. Testinghe best to use inm other uses, and.nt, For example,ms of operational.he fact that theyuctance to pursuepment should be

.sualty estimation

g when the earthhe or she do aftersent a learned reJr is appropriate?luable advice that;tioos must be obthodologies which1 to those relatingit behavior do ex'9 Imperial Valley

jury epidemiologyhich may enhanceaeral; it is possible; raised, however,nder stress. Moreof more effective

1S checking for gas


and water leaks after the earthquake than teaching appropriate behaviors during theimpact phase.

One issue raised during the discussionswas how does behavior interact with theother factors in influencing survival? For example, the design of escape routes in abuilding should reflect behavioral as well as structural considerations.

While much discussion is focussedon individual victim/occupant response, it wasnoted that organizational response is important, and its linkage to individual response. For example, how are rescue activities affected by the emotional responsewhich follows a devastating earthquake? The behavior of i~dividual rescuers alsoneeds to be studied: what was their response, and was it modified by training? Abody of research and experience exists on the mental health consequencesof disastersboth with regard to the the victims and the effect on SAR personnel. More detailedresearch in earthquake situations is needed.

Injury Issues

cl::I.ikc:

injuries" and "earthquake deaths." Heart attacks are often claimed as induced byearthquakes. On the other hand, it is possible that deaths resulting from power

fa:i 3'j not b rclate:i:l.

While it was suggested that injury could be defined by indicators or signs, such as"requiring medical care" or "requiring hospital care," rather than by using diagnoses,it was noted that these definitions will vary across cultures, perhaps making themunreliable. To correlate building types with injuries, types of injury, and injuryseverity is important, as well as the number and distribution of injuries, It wasnoted that both types and numbers are important for the estimation of supplies andpersonnel needs. Such a classification system must be field applicable. More workneeds to be done to develop simple severity measures (14). However, distinctionsshould be ~ade between those requiring hospital (or emergency shelter 24-hour care)and those treated as outpatients. At present, this represents the best simple indicatorof severity available.

Assessment of the number of out-of-hospital deaths is extremely difficult. Also,backtracking injuries from hospitals to specific buildings poses major problems. The

N. P. Jones, F. Krimgold, E. K. Noji, and G. S. Smith Considerations in522

The use of injury severity scores as a means of providing detailed quantitative.injury data was strongly advocated. Two different types of injury may generate identical injury severity scores, but the interventions they demand may be quite different.It was suggested that there needs to be a larger database of detailed descriptive dataon earthquake injuries. How do victims of collapsed structures differ from standardtrauma victims? Can the data used from motor vehicle injury studies be extrapolatedto trapped earthquake victims?

Appropriate interventions for various injuries or conditions need more researche.g., what are the best treatments for victims of crush syndrome? Do tranquilizersavoid the so-called "rescue death"? Animal models are currently being 'used to studycrush and asphyxiation injuries and their treatment. What is the pathophysiology ofthe dying process? Research in resuscitation methodology (e.g., the role of surgery)is needed. How can it be determined if amputation is necessary? Laboratory andclinical studies are needed, as clinical research is difficult to do under pressure ofresuscitation. Development of standards for treatments in disaster situations willimprove aggregate medical response in such events. New specifically-designed EMSequipment must be developed, and widely applicable to enable production. This isneeded for both intensive individual care and standard mass care situations. Progressin disaster medicine may also lead to improvements in non-disaster EMS techniques.

A somewhat separate, but related, topic is the study of injuries to rescue workers, both volunteer and professional. Of particular interest are the mental healthconsequences of those involved in the stressful and demanding rescue process.

The possibiliin structures wa

potentially fruitin the automobto safer vehiclesWhile shaking .frequently usin;structural engirwas noted thatWhile not tradand housing mr

A related isios. These disaexercises, home

ganizational re:

and have provelevels of responand operationa

SAR Operational IssuesThe genera'

discussed. Intecritical phasesgathering and

It was conseration be giveand response.shown that mi

must be awareor suspected cimmobilized.

Possible avnoted that res!data discussed

Some discussion 'occurred relative to operational organization and the IncidentCommand System (ICS). Past experience with ICS indicated that it worked bestwhen applied to situations for which it was designed. It was questionable whether anevent such as an earthquake affecting a major city fell into this category. Problemswith ICS have been identified during both disasters and drills. It was suggested thatICS be thoroughly reviewed to ascertain whether it is adaptable to this context, andif not, develop a more appropriate system. It is noted that a significant strength ofICS is planning. Whether development of centralized or decentralized organizationin the response phase is desirable and appropriate was debated. Is it better to buildon existing emergency resources or to create a specialized disaster response center?

,foji. nd C. S. Si'itilli

ailed quantitativelay generate idenbe quite different.d descriptive dataFerfrom standardes be extrapolated

Experimental Issues

ed more researchDo tranquilizers.ing used to studyathophysiology ofe role of surgery)Laboratory andlnder pressure ofer situations willlly-designed EMS:>duction. This isuations. ProgressEMS techniques.s to rescue workhe mental health

The possibility of using experiments to study various aspects of the injury processin structures was discussed. Full-scale testing and modeling of structures was seen aspotentially fruitful. It was noted that this approach has been used with some successin the automobile industry, where crash tests, using instrumented dummies, has ledto safer vehicles through improved structure performance and better safety devices.While shaking tests using tables and reaction walls with model structures, and lessfrequently using full-scale buildings, have been performed; their focus has been onstructural engineering. No injury modeling has been performed, except in Japan. Itwas noted that studies of this type do not realistically account for behavioral effects.While not traditionally considered "engineered structures," experiments on houses,and housing materials and components are needed to improve life-safety.

A related issue, which may be considered "experimental" is the use of scenarios. These disaster simulations can be made at various levels (e.g., workshops, fieldexercises, home safety drills) and can be used to test, in particular, behavior and organizational responses. These have been used successfully,for example, in California,and have proven to be powerful tools. In addition to providing exposure to variouslevels of responders to "realistic" disaster situations, studies made of the proceduresand operational effectiveness can augment the databases in this area.

General Research Issuesue process.

and the Incident.t it worked bestnable whether antegory. Problemsas suggested thatthis context, andScant strength ofized organizationit better to buildesponse center?

The general question of the need for and effectiveness of international help wasdiscussed. International help must be considered a backup to local response in thecritical phases. It was suggested that international responders are a resource forgathering and dissemination of information .

It was considered important, in light of the above comments, that serious consideration be given to training both local responders and communities in preparednessand response. There are difficulties: the numbers of people are large; experience hasshown that much of the information is not retained. Rescue workers, in particular,must be aware of the "dos and don'ts" of light rescue: e.g., patients with potentialor suspected cervical spine injuries should be moved only after the neck has beenimmobilized.

Possible avenues include the linking of training to the place of employment. It isnoted that rescue work must start immediately, with or without the rapid assessmentdata discussed above.

524 N. P. Jones, F. Krimgold,E. K. Noji, and G. S. Smith Considerations in th.

A large number of rescues are always self-rescues, or are performed by volunteers.Planning for integration of local volunteers into the rescue effort should be takenseriously. The capacity of such resources should not be underestimated, and in factshould be considered when evaluating an appropriate response. Information on localEMS resources available is also needed in such an assessment. An important questionis how is the communication between formal and informal groups established andhow can it be made more effective? Should we, for example, be training formal SARpersonnel in methods of coordinating volunteer teams rather than concentrating onindividual rescues?

The SAR issue is a complex one. SAR is not always needed. Nor does it alwayssave the most lives. Nor is it necessarily "cost effective" when compared with mitigation measures. Public pressure may demand the implementation of professional SARefforts, even though few, if any, persons remain alive. It is viewed by the public as aheroic response, and its presence, whether particularly effective or not, is necessary.Extrication difficulties with trapped victims still clearly pose a major problem, evenif the numbers involved are not necessarily large. In terms of resource allocation,however, an important fundamental question which must be addressed is whetherimproved SAR technologies can save significant numbers of lives?

Research in SAR and how to improve its overall effectiveness is therefore necessary.Coordination of SAR resources is often a problem; specialized personnel are neededfor heavy SARj can SAR teams be certified? It is noted that resuscitation and lifesupport should be part of SAR: The process should be designed accordingly. Whatcan we learn from other SAR situations such as mine rescues?

the integration of e

research is likely t<It is anticipate

also be applied toPrincipal nee'd

1. The developon injury, st

2. The studygathering d

3. The prepa:

designed st

4. The develoment.

Conclusions

Principal furdation (NSF), sDivision of CritNational Center6010 and 88-401for Internationaacknowledged.

The International WorkJhop on Earthquake Injury Epidemiology for Mitigationand Response held at The Johns Hopkins University in July, 1989 was an importantfirst step in defining the field of earthquake injury epidemiology, outlining potentialinterventions which cou~dbe based on research findings, and reaching some agreementon data collection needs and methodologies. The workshop, as outlined in the abovepaper, did not provide answers to all the important problems associated with thestudy of approaches to reduce the health consequences of earthquakes. However,it has provided a clearer understanding of many of these problems and of possibledirections for future research. To effect reductions in earthquake casualties in futureevents, contributions from many professions must be integrated and implementedin a rational and consistent manner. Just as epidemiology and other public healthprinciples have provided important new insights into the study of disease processes, so

1. Alexande- 60.

2. de BruycItaly: Re1021 - 1C

3. de BruyHaly: M117.

l by volunteers.

aould be taken

ed, and in fact

nation on local

ort ant question

.stablished and

ng formal SAR

'llcentrating on

the integration of epidemiologic techniques to other disciplines involved in earthquake

research is likely to lead to better methods to reduce casualties in future earthquakes.

It is anticipated that the lessons learned addressing the earthquake problem mayalso be applied to other natural (and technological) disasters.

Principal needs identified during the workshop were:

1. The development of standard data collection forms which can incorporate dataon injury, structural collapse and SAR response.

does it alwaysed wi th mi tigaofessionalSARthe public as at, is necessary.problem, eventree allocation,sed is whether

2. The study of historical events, in particular recent events, with a focus ongathering data on the above topics.

3. The preparation for data collection in future events and planning for welldesigned studies in anticipation of an event.

4. The development of functional models for casualty estimation and needs assessment.

efore necessary.nel are needed.ation and liferdingly. What

Acknowledgements

Principal funding for the workshop was provided by the National Science Foundation (NSF), grant number CES-8815609, through Dr. William A. Anderson of theDivision of Critical Engineering Systems. Additional support was provided by theNational Center for Earthquake Engineering Research in Buffalo, grant numbers 88-6010 and 88-4005, the Office of U.S. Foreign Disaster Assistance of the U.S. Agencyfor International Development, and the Hoechst Company. This support is gratefullyacknowledged.

for .Mitigation; an important.ning potentialorne agreementd in the aboveiated with theces. However,nd of possible'1.1ties in futurel implementedpublic health

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2. de Bruycker, M., Greco, D., Annino, I., et al. "The 1980 Earthquake in SouthernItaly: Rescue of Trapped Victims and Mortality." IFHO Bulletin 61(6), 1983.1021 - 1025.

e processes, so

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N. P. Jones, F. Krimgold, E. K. Noji, and G. S. Smith526

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Approaches and Issues for Future Research." P-350 - P-365.illowing Earth-

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5.-528 N. P Jones, F. Krirngold. E. K. oji, and G. S. Smith

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BvaluaticSeismic ~

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W. F. Marc:

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Ever sinceand Niigata, Jcduring earthquunderstandingExcellent surruand state of thby Yoshimi etResearch Cow

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41. Hays, W.W "Data Acquisition for Earthquake Hazard Mitigation." P-494P-502. As a resu.

February 1971the Lower Saninvestigations,embankment (

(WFM,1'.Experiment St

Documents

Considerations in the epidemiology of earthquake injuries