Methodological considerations should be discussed within the context of emergency medical services (EMS) and disaster research. The fast pace and the information explosion of the society in which we live open new opportunities for epidemiological research and evaluation of care in disasters. The many methodological considerations necessary to generate useful and valid research is the topic of this article.

I would like to discuss four major issues which raise a series of questions and suggest a variety of alternatives. The four major areas are: (l) the taxonomy required to do this type of research; (2) the elements of care; (3) comparative samples; and (4) planned as opposed to unplanned disasters.

In Sweden as in most countries there has been an increasing use of airborne transports for medical purposes during the last decade (Fig. 1). The majority of these transports have been made by helicopters. The climate and the geographical position of Sweden in the far north of Europe presents problems to a helicopter rescue organization. The area of Sweden is approximately 400,000 square kilometers, which is a little more than that of Italy and less than that of France. There are about 8.5 mill, inhabitants which means an average of 20 per square kilometer. The population is unevenly distributed. There are only three densely populated areas: around Stockholm, around Gothenburgh and in the southern most part of Sweden with 250 respectively 150 inhabitants per square kilometer. In the middle and in the north of Sweden there are less than 5 persons per square kilometer. In the mountain regions there are even less. Temperatures ranging from about +25°C in summertime to below - 20°C in the winter are not uncommon.

There is a nationwide alarm system with a common telephone number for all emergency situations and alarm centers, which direct a call for assistance to the proper rescue organization. Almost all medical services in Sweden are provided by regional governments. Adequately equipped and staffed hospitals exist all over the country. The roads are generally of good quality, but outside the urban areas the distance from the place of an accident or a medical emergency to a hospital is usually great.

One of the most important aspects of disaster planning is providing for early availability of medical equipment, partly stored at the airport and partly brought from outside. The first priority is obviously to evaluate what is required.

Correct Medical Strategy. This is based on the concept that the first priority is to care for the injured whose life is in immediate danger. The activity on site will include: triage, simple at the beginning, based on first aid concepts, but more sophisticated as more experienced personnel become available; on site care, ranging from first aid to resuscitation; and a rational dispatching of patients to hospitals, using resuscitation ambulances, specially equipped helicopters, or standard ambulances.

Classification of Victims. Priority I or red tag. Priority II or yellow tag. Priority III or green tag. Priority IV or black tag (dead).

Wars have contributed to the progress of emergency medicine. Napoleon's surgeon Larrey introduced a new era in surgical skills. During World War I, blood transfusions and anesthesia were introduced, and during World War II, penicillin. Neither in war nor in civilian disasters can one predict the number of casualties. Thus planning should be similar.

The aim of this planning project is to ensure prompt and efficient emergency health services to all people in the regional territory of Tuscany, and to establish suitable conditions for an efficient intervention by the National Health Service in situations brought about by unforeseen events which may have serious, often disastrous, consequences. This effort — quite demanding from an organizational and economic point of view — may be successful only if we assume that the time-space unpredictability of emergencies cannot be understood in absolute terms, but in relation to a series of conditions and situations present in everyday reality. Only by reducing to the minimum the unpredictability factor both quantitatively and qualitatively this purpose can be achieved. Risk factors should thus be accurately related to the territory's population distribution, geomorphology, and socio-health conditions.

Since emergency medical care must be carried out without delay, each response must involve all components, concomitantly or in sequence so that the intervention is not regarded as concluded at any one stage. It must be open to integration best suited to the situation. There is need for a multidisciplinary approach to emergencies from the first response to definitive care.

The model of health services planning necessary to achieve all this envisages a series of interventions — 1) to develop interconnections between intramural medicine and health services carried out in the field in order to allow rational use of existing structures, such as the emergency department; 2) to establish coordination focal points which can ensure, outside a hospital, the same level of treatment in emergency situations that will be carried out intramurally, despite the unavoidable changes in methodology; and 3) to activate information and self-training programs designed to encourage the development of a cultural and operative relationship between the health services and the needs of the community.

The development of emergency medical services (EMS) systems in the United States, incorporating various levels of sophistication in prehospital care and echelons of capability in hospital resource availability, has brought new connotations to the word “triage” (sorting).

Heretofore, triage consisted entirely of estimating treatment needs so that prioritized transfer of patients could be made to hospitals. The decision is no longer binary, since the introduction of Trauma Centers requires the triage decision maker to not only decide which patient first, but also which patient to which hospital. Clear cut decision rules for this process applied to routine civilian emergency medical practice have yet to emerge.

Some two years ago the Club of Mainz Executive Committee endorsed a proposal to investigate the rescue and medical facilities at a selection of the world's airports. A number of members of the Club agreed to take part in a survey of a sample of airports in their own regions and some of these reports will be presented in this article. Three airports were studied in the United Kingdom — London Heathrow and Stansted — both civilian airports, and one military airport, Brize Norton, in Oxfordshire.

London Heathrow is one of the biggest international airports in the world, handling more airlines than any other. More than 25 million passengers a year pass through Heathrow and at peak periods there are up to 78 aircraft arrivals and departures per hour. More than 60,000 people are employed at Heathrow. A wide variety of planes are handled from Concorde and wide-bodied jets to small executive aircraft.

Stansted Airport is situated some 30 miles north of London and is also a standby airport for both Heathrow and London's second airport, Gatwick. At present only 500,000 passengers use the airport each year, but it has a capacity for four times this number and there are facilities for further expansion. Stansted is also the fourth biggest air cargo handler in Britain and caters to a complete range of aircraft.

EMS in developing countries must be established as a high priority, since it is one of the key elements in making possible any realistic improvement in health care. In Egypt, the pre-hospital phase of EMS is a highly visible commitment to the welfare of the nation and is a catalyst for other health activities. Satisfying needs identified in rural health care, such as high-risk infants, trauma, and time-related health problems, will be facilitated by an effective EMS system. EMS must be adapted to fit the culture of the people and their specific needs.

A disaster may be defined, for this paper, as “a situation in which an urgent need arises for international assistance to relieve humansuffering.” Disasters are frequently divided into manmade and natural disasters. Many so-called natural disasters have, however, a considerable manmade component in their etiology. The number of people vulnerable to the effects of disasters is increasing, and in the future disasters affecting human beings are likely to occur with greater frequency and severity, Full account must also be taken of the effects of a rapidly expanding world population, of advances in science and technology, and of economic and ecological factors.

Our ability to manage disaster relief activities at regional, national or international levels of socio-political organization has, according to many analysts, not kept pace with the knowledge and technical capability presently available to contend with disasters. In a report released in 1977 a panel of experts assembled by the United Nations Association characterized disaster relief efforts as being routinely mismanaged. For example, the panel described what has been considered one of the better organized disaster relief efforts (the 1976 earthquake in Guatamala) in the following way.

The Disaster Planning for Stansted Airport, which' it is proposed will become London's third airport, with expansion to handle up to 50 million passengers per annum by the end of the decade, poses a unique problem because, unlike most other major airports, it is relatively isolated and some distance from the medical facilities required to handle a major disaster. The airport is situated about halfway between London and Cambridge, each 30 miles away, in the heart of the countryside in North Western Essex, close to its border with Hertfordshire.

In the past, the number of survivors from aircraft accidents involving narrow-bodied jets has been very small but, with the advent of the wide-bodied jets such as the Boeing 7k7, this has changed and survival rates in excess of 50% have been found. This gives a potential of more than 250 survivors from an aircraft with 500 seats, many of whom might be expected to have major injuries.

The nearest hospital is k miles away which, in the event of a major disaster, could take up to 6 seriously injured and 12 walking wounded within the first 4 h. Twelve miles away is another hospital which could take the same number, and 20 miles away is a further hospital which could handle up to 8 seriously injured and 20 walking wounded. The nearest hospitals with major accident departments are in North East London and Cambridge, each of which could take up to 10 seriously injured and 50 walking wounded initially.

By definition, hospitals should be among the places with the highest safety index (1). But often, on these premises, we have occasional accidents which may be dangerous and which illustrate the way hospitals are exposed to various and often undervalued risks.

The incidences of unforeseen, dangerous situations involving sudden accidents, of uncontrollable emergency conditions and also of larger catastrophes are awful. Recent accidents proved inadequate safety inside hospitals. In Parma (2) escaping gas was followed by an explosion that destroyed a division of the hospital and resulted in wounded and dead. In Mondovi, an explosion in the central heating system of the hospital caused the death of an employee. A fire that broke out in an old people's home in Southern Italy brought about the death of three persons. The first shocks of the earthquake in 1980 caused the death of many patients and staff (including six physicians) in the so called “safe” hospital of San Angelo Dei Lombardi. In the earthquake in 1976 many patients and some personnel of the hospital staff in Gemona, Friuli lost their lives (3)

Apparently these facts are not closely linked together. Some were caused by human error, others by inadequacy of buildings, age of structures, even where the disaster was due to natural causes. However all these events show the presence of the common denominator of “high risk,” typical of hospital structures (4,5). The principle dangerous situations are: (a) risks coming from the structures of the premises (no earthquake-proof principles of modular structure); and (b) risks connected with the working activities (6,7).

In war a large number of military and civilian wounded and injured patients, and patients with disease, will increase the strain on the system of medical care. The expected distribution of injured in a conventional war can be estimated on the basis of previous war experiences, especially from World War II (1), the Korean war (5), the Vietnam war (7, 8), and the Arab-Israel wars (3). Corresponding figures for the civilian population are less readily accessible. Statistical data from previous wars as well as expected weapon development can be compared with data from various peacetime accidents and disasters. Thus, the expected distribution of injuries can be estimated (Table 1) (7).

A Controlled Clinical Trial is the formal experimental approach to treatment evaluation. In such a trial, the investigator controls the assignment of treatments—ideally by randomization— to experimental groups. When well executed, such a trial provides the strongest evidence for the relative effectiveness of the different therapeutic interventions. Some people, myself among them, believe that the clinical trial approach should be used early when a new therapeutic modality is first introduced.

The purpose of a controlled clinical trial is to answer the question of whether the new therapy is preferable to standard therapies. If no standard therapy exists, then new therapy has to compete either with no treatment or placebo.

Up to 1980, the important European airports and European airlines increased the number of their flights and passengers. As a result, it has been necessary to develop and launch airplanes with a high passenger capacity (e.g., Boeing 747, Jumbo, with 270 seats; Douglas DC 10 with 265 seats; and the Airbus A 300 with 249 seats). Simultaneously, the airports had to be enlarged or even rebuilt. After this substantial investment, the number of passengers began to decrease. In 1981, the French airline “Air France” expected a deficit of about 65 million DM (29.5 million US dollars), excluding the deficit by Concord. For the first time in 18 years, the Scandinavian airline “SAS” in 1980 had a deficit. The German airline “Lufthansa” expects no profits in 1981. This situation has been caused by rising oil prices, decreasing numbers of passengers, and a general recession. Many airlines have been reducing prices to attract more passengers. In spite of the high investments in new airplanes and modernizing airports, there has been little improvement in the necessary air- and ground-control-systems.

In April 1981, the International Associates of Pilots (IFALPA) graded the security of air- and ground-control-systems of German airports as follows: deficient — Frankfurt and Bremen; seriously deficient — Hamburg, Stuttgart and Saarbrücken. According to the security scale of the IFALPA, the most important airports in the Mediterranean area were surveyed and estimated in 1977/78 as follows: deficient — Los Rodeos (Canary Islands), Las Palmas (Canary Islands), Lisbon, Faro, Malaga, Alicante, Madrid, Gerona, Ibiza, Palma de Mallorca, Venice and Roma; and critically deficient — Alghero, Rimini, Naples.

Our belief that there is a superagency that goes to work when a disaster occurs is unfounded. What does exist is a network of integrating expertise and resources that are escalated from different routine activities to cooperatively respond to one event. This paper concerns the governmental approach in one area, New York City.

In the United States, federal and state laws exist to minimize the effects of disasters, by identifying measures to prevent or mitigate them, developing mechanisms to coordinate the use of resource and manpower during disasters, and by providing recovery and redevelopment following a disaster. These functions and services are coordinated to the maximum extent with comparable activities of local state and federal governments, and many voluntary private agencies. Organizational responsibility follows a bi-directional flow from federal to state to county-, city-, town- and village level, and in the reverse (Fig. 1). The roles and responsibilities depend on the type of disaster (Fig. 2) and hence the response and activity needed. Response activities include need for clothing, crisis counseling, debris removal and disposal, disease and pest control, equipment and supplies, evacuation, food provisions, fuel provisions, housing and shelter, identification and disposition of the dead, labor pools, law and order, medical care and treatment, power provision, protective measures, search and rescue, sewage control, transportation, the need to waiver codes, water provisions, and weather forecasting.

International organizations such as the World Association for Emergency and Disaster Medicine (Club of Mainz) have brought attention to the need for improved worldwide emergency medical services (EMS) systems and disaster preparedness (1). Similar concerns in the United States (US) for improved emergency medical care have resulted in the organization of emergency medicine as a new medical specialty (2). The practice of this specialty of medicine in some ways differs from the practice of emergency medicine, reanimation medicine, or resuscitology, in Europe. In the United States, emergency medicine specialists provide emergency care for the full range of emergency health conditions, including accidents and trauma, medical emergencies, toxicologic emergencies, psychiatric and social emergencies, and disasters. This care is provided primarily in hospital emergency departments and includes the immediate initial recognition, evaluation, treatment and disposition of these patients with acute illness and injury. For continuing care, patients are referred to their own physicians.

Emergency medicine physicians provide medical direction for community EMS and supervise the prehospital emergency medical care provided by non-physicians (emergency medical technicians and paramedics). Emergency physicians engage in the administration, research and teaching of all aspects of emergency medical care. They also provide consultation to governmental and nongovernmental organizations on emergency health care issues. Recently, with the basic framework of emergency medicine established, attention is being given to disaster planning and management.

Trends in recent warfare show a movement in the proportion of wounded soldiers to wounded civilians from 20:1 in World War I to a conjectured 1:100 in the case of atomic, biological or chemical warfare. Modern methods of waging war mean that for every fighting man, a group is engaged in logistics, and that for every dead soldier, an increasing number are wounded. Furthermore, the number of severely wounded cases is proportionately increasing.

During peak hours at Frankfurt Airport, approximately 10,000 employees of 300 different firms, organizations and services simultaneously handle more than 10,000 passengers and accompanying people. Most of them are not familiar with the airport facilities and speak several different languages.

Disaster management is the act of solving an organization problem under pressure of time. The leading role during the immediate action concerning major accidents or disasters is played by the Safety and Security Control Center of the airport operator, which alerts and controls all emergency services of the airport. Included in this organization are the fire-fighting, rescue and medical services of the airport operator, the U.S. Rhein Main Air Base and the emergency services of the City of Frankfurt. The immediate actions are exclusively based on the operation of professional task forces (without volunteer helpers). As far as possible, the emergency procedures, including personnel operations, are the same at all hours (working/holidays, day/night).

The basis for the emergency operation is the “Emergency Orders” manual. The manual consists of an alarm plan in the form of alarm checklists for the different emergency services and of emergency procedures which are activated through the alarm plan.

Command and control through the staff and communication system of the Safety and Security Operation Center, the on-scene Mobil Command Post and the operation centers of the airport services guarantee that the immediate response of the airport's and external task forces is fully coordinated without delay.

In an emergency medical services (EMS) system, a certain number of events come to the attention of the pre-hospital subsystem that are subsequently characterized as having required “life-supportive” care. Such cases represent an undetermined portion of the persons, in the population served, who actually require such care. Generally, the life-support units that are available in a community are dispatched on the basis of information received at a medical emergency dispatching center. Very often, the information obtained from the caller is too ambiguous for a clear decision and, inevitably, there is a significant portion of “false-positive” or inappropriate runs. In systems in which little or no attempt is made to screen calls, the dispatching procedure inevitably becomes a “first come, first served” phenomenon and the inappropriateness of the responses is bound to be even greater.