Journal of Natural Disaster Science, Volume 33, Number 1, 2012, pp1-10

Injury Estimation for Foreseen Earthquakes in an Aging Society and
Its Application to Sendai City, Japan
Takeshi SATO*
Masatoshi OBA**
Yotaro SHINOZAWA***
Akira MANO*
Masato MOTOSAKA**Disaster Control Research Center, Tohoku University, Japan**Emergency Center, Osaki Citizen Hospital, Japan***Emergency Center, Tohoku University Hospital, Japan(Received April 5, 2010 Accepted August 7, 2011)
ABSTRACT
Society is aging rapidly in Japan. For disaster mitigation against periodic earthquakes
based on asperity theory in seismology, the transition of the social environment should beconsidered in the intervals between periodic events. This paper focuses on the aging ofsociety as an important expansion factor in human injury. The major objective of this paper
is to estimate the effects of aging on injury including serious cases caused by earthquakes.
In this paper, three age classes are used as follows. Young age is defined as the generation
under 14 years. Old age is defined as 65 years old or over. Middle age is defined as theother group. This classification is often used by the census.
Sendai City as the Miyagi prefectural capital is selected because it is one of the mostearthquake-prone regions in Japan. The main earthquake to hit the region is the Off Miyagi
earthquake with a magnitude about 7.5 Mj. This event has periodically struck Sendai City at
average intervals of about 37 years.
A few assumptions are made in estimating the injury rate as a result of an Off Miyagi
earthquake without a tsunami. Firstly, the normalized injury ratio proposed by the authors
can be applied to estimate the injury rate for a foreseen earthquake. Secondly, the injury ratein each age class as a result of an expected Off Miyagi earthquake can be assumed to be thesame as in the previous event in 1978. Finally, only the transition of the population structure
regarding multiple factors can be considered in the interval between periodic events. In
addition, the emergency response load of taking care of the injured elderly is proposed.
(1) In the subject region in Sendai City, the ratio of the old-age population divided
by the total population has increased three and half times in the 30 years from theprevious Off Miyagi Earthquake in 1978.
(2) The normalized injury ratio in the old-age class was evaluated as being two and halftimes that in the middle-age class.
(3) The percentage of injured in the subject region in each age class during the Off
Miyagi Earthquake in 1978 was reproduced.
(4) Under the assumed occurrence of the expected Off Miyagi earthquake in 2005, the1

T. SATO, M. OBA, Y. SHINOZAWA, A. MANO, M. MOTOSAKA

number of injured in the subject region in each age class was estimated considering
the increase in the population and the progress of the aging of society. The numberof injured has increased five times in the past 30 years. The year 2005 was adopted
as the assumed occurrence year of the earthquake because the fiscal year of thenewest data that have already been published as population statistics of the census
was 2005 at this submission.
(5) The emergency response load of taking care of the injured elderly was evaluated.
The load of the middle age has increased approximately three times in the past 30
years.
Keyword: Earthquake disaster, Human injury, Aging society, Off Miyagi earthquake
Keyword: The injury potential due to periodic Off Miyagi earthquakes has been influenced
by the aging of society. The main conclusions obtained are as follows.

1. INTRODUCTION

Hanshin Earthquake in 1995 and the individual countermeasures by elderly residents living alone in thesuburbs of Tokyo. Injury prevention by older people
was identified as an important problem. Lu and Miyano (1998) analyzed the transition of total deaths during major earthquake disasters in the past century inJapan for every decade in age. Vulnerability functions
in human injury by earthquakes were proposed by
Ohta and Ohashi (1986) as pioneers, by Shiono andKosaka (1986), by Shiono and Krimgold (1990), by
Lu and Miyano (1995), and so on. However, the effectof age on human injury is studied in a limited way. Asa previous study, Kataoka (2004) performed an injury
estimation during an earthquake considering the ratioof elderly persons. But concerning vulnerability toinjury by age, daily life data by Naoi and Uno (1991)
were substituted for the earthquake disaster. Physicalseismic damage such as to building structures from a
new viewpoint of considering the temporal and spatial
growth of a region was estimated by Okada and Ohta
(1998). They suggested the importance of long-term
land use planning, especially in urban areas and thevicinities, in consideration of the time dependency ofrisk potential on the receiver side as well as seismic
activities influencing the region.
The major objective of this paper is to estimate
the effects of aging on injuries including serious cases
caused by earthquakes. An outline of the estimation
method is presented as follows. The contents of injuryclassified according to young, middle, and old age are
analyzed for the latest earthquakes in Miyagi Prefecture. Data on the injured with age attributes during
the 2003 Northern Miyagi Earthquake and the 2008

Miyagi Prefecture is one of the most earthquakeprone regions in Japan. The Earthquake ResearchCommittee under the Japanese government evaluatedthe occurrence probability of earthquakes on major
active faults and subduction zones in Japan. The Off
Miyagi earthquake with a magnitude of 7.5±0.1 Mj(JMA scale) is one of the major earthquake scenarios
for Miyagi Prefecture. The occurrence probability
within 10 years is around 70% based on the estimation on January 1st, 2009. Events with a magnitude ofabout 7.5 Mj have periodically struck Sendai City as
the prefectural capital with a one-million population
at average occurrence intervals of about 37 years. The
previous event with a magnitude of 7.4 Mj occurredon June 12th, 1978. Sendai City is selected as the subject of analysis in this paper.
For disaster mitigation against periodic earthquakes based on asperity theory in seismology, both
reduction and expansion factors should be consideredin the interval between periodic events. This paper
focuses on aging society as an important expansion
factor in human injury. The old-age population defined as being the generation older than 65 is growing
rapidly in Japan, including Sendai City. The old-age
group occupied 5% of the whole population of Sendai
City in 1978 when the previous Off Miyagi Earthquake occurred, while it now reaches 18%, 30 years
from the previous event.
Disaster mitigation problems in an aging society
were discussed by Kosaka et al. (1995) based on asurvey of the actual damage situation during the Great2

INJURY ESTIMATION FOR FORESEEN EARTHQUAKES IN AN AGING SOCIETY AND ITS APPLICATION TO SENDAI CITY, JAPAN

Iwate-Miyagi Inland Earthquake were collected by theauthors. Young age is defined as the generation under
14 years. Old age is defined as 65 years old or over.
Middle age is defined as the other group. The injury
rate is defined as the ratio of injured persons in every
age class to the whole population. The normalized injury ratio by dividing the injury rate in every age classby the middle-age class is proposed by the authors.
The number of injured in every age class during the
Off Miyagi Earthquake in 1978 is estimated by applying the proposed normalized injury ratio, because
the records lack detailed attributes of the injured. Twoassumptions are used in the injury estimation for expected Off Miyagi earthquakes. Firstly, the injury rateof the middle-age class in the expected Off Miyagi
earthquake is the same as in the previous Off Miyagi
Earthquake in 1978. Secondly, the normalized injury
ratio proposed by the authors can be used for any
foreseen earthquake. Also, the emergency response
load of taking care of injured elderly people by the
middle-age group is calculated. Finally, human injury
problems due to the aging of society are discussed.

collapsed houses to the total number of houses in the
Rokugo region was the highest in Sendai City at approximately 1.5%. Even if the number of houses in
the Rokugo region comprised only 3.5% of the total
in Sendai City, the number of damaged houses in the
Rokugo region reached 22.7% of the total (Abe et al.,1983). The data suggest that the Rokugo region was
exposed to the earthquake’s strong ground motion ina natural environment.

Fig. 1 Topographical classification map around the alluvial plain in Sendai City

2. REGIONAL CHARACTERISTICS OF THE
RESEARCH SUBJECT

2.2 Change of social environment
The Off Miyagi earthquake with a magnitude ofabout 7.5 Mj periodically strikes the Rokugo area ataverage occurrence intervals of about 37 years. There
were eight small villages in the Rokugo region in the
1880s. Rokugo Village was born by the merger of eightvillages in 1889. Half a century later, Rokugo Village
was amalgamated with Sendai City as a neighboring
big city in 1941. Some areas in Rokugo were designated as areas for urbanization in 1973. The Off Miyagi
Earthquake in 1978 struck the urbanized Rokugo area.
The number of households in Rokugo over about
the past 200 years is shown with the occurrence timeof the periodic Off Miyagi earthquake in Fig. 2. Figure 2 suggests the situation of sudden urbanizationfrom the 1970s. The broken lines in Fig. 2 indicate
the occurrence times of the periodic Off Miyagi earthquakes. In the 200 years up to the 1960s, the increasein the number of households was only four per year on
average. The number was approximately 240 per year
in the 13 years from 1965 to 1978 when the previous
Off Miyagi Earthquake occurred. The rate has slowed
recently, although the increase trend is continuing.
The Rokugo population by age class over about
the past 50 years is shown in Fig. 3. The population

2.1 Natural environment
Sendai City is located almost in the center of Miyagi Prefecture and stretches from the Ou Mountain
Range in the west to the Pacific Ocean in the east.
The city area in Sendai has been developed upon thetableland and the river terrace lands formed by theHirose, Natori, and Nanakita Rivers. A part of the alluvial plain in Sendai City is shown in Fig. 1 (Sendai
City, 1994). In the earthquake investigation report by
Sendai City (2002), strong ground motion equal to or
larger than 6-lower on JMA’s seismic intensity scale
was estimated against the expected Off Miyagi earthquake because of the unconsolidated ground condition. Districts with high statistical seismic risk in the
expected Off Miyagi earthquake obtained in the Japanese national census are very few, and they include
Takasago, Shichigo, Rokugo, and so on. Rokugo isspecially selected as a high-risk area in Sendai City.
The Rokugo area is indicated as the area encircled by
the dotted line in Fig. 1.
During the Off Miyagi Earthquake in 1978, thehouse damage rate as a ratio of severely damaged and3

T. SATO, M. OBA, Y. SHINOZAWA, A. MANO, M. MOTOSAKA

of only the old-age group continues its increasing
tendency though the other classes have already passed
their peak. The number of those in the old-age classexceeded those in young-age class in 2005 and the
middle-age class in 1960. Rokugo began to take on
the serious character of being an aging society. Because of this situation, the extension of human injury
risk is of concern.
㻝㻤㻟㻡 㻝㻤㻢㻝 㻝㻤㻥㻣㻝㻣㻥㻟㻺㼡㼙㼎㼑㼞㻌㼛㼒㻌㼔㼛㼡㼟㼑㼔㼛㼘㼐㼟

㻝㻞㻜㻜㻜

㻝㻥㻟㻢

The reduction of physical risk such as structural
damage to housing is considered, because most of the
housing in the area had been built with the newest
seismic design code from 1981 after the previous Off
Miyagi Earthquake in 1978. But, on the other hand,because the population is exposed to strong groundmotion as the natural hazard increased after 1978, theexpansion of human injury risk is a cause of worry.

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㻞㻜㻜㻜

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Fig. 2 Transition of the number of households andearthquake occurrence years over about thepast 200 years(a) 1928㻟㻜㻜㻜㻜㻼㼛㼜㼡㼘㼍㼠㼕㼛㼚

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Fig. 3 Transition of the population by age class overabout the past 50 years(b) 1977

2.3 Change of land use
Land use maps around the urbanized Rokugo
area over about the past 70 years are shown in Fig.
4. Figure 4 (a) shows that the area was only a farming village in 1928. With an area designated for urbanization, the area was connected to the urban areain Sendai City in the 1970s. Land use after 50 years
from the time point in Fig. 4 (a) is shown in Fig. 4 (b).
The previous Off Miyagi Earthquake occurred justafter the circumstances shown in Fig. 4 (b). Most of
the Rokugo area locates the back damp on geography.
The state of land use after 20 years from the eventin 1978 is shown in Fig. 4 (c). It is clear that the cityarea was extended to the suburbs in soft-ground areas.

(a) 1998
Fig. 4 Land use maps around the urbanized Rokugo
area over about the past 70 years
Figur(Japan Map Center, 1998)
4

INJURY ESTIMATION FOR FORESEEN EARTHQUAKES IN AN AGING SOCIETY AND ITS APPLICATION TO SENDAI CITY, JAPAN3. RESULTS AND CONSIDERATION

tion, that is, the young-aged, middle-aged, and oldaged classes. The injury rate increases for the oldage group (65 years old or more) to reach 2%. Similar
data during the 2008 Iwate-Miyagi Inland Earthquake
are shown as the black circle in Fig. 5. The data
were newly collected in the Tsukidate district by theauthors in cooperation with the Medical Bureau of
Kurihara City. Tsukidate is a major district in Kurihara City. Both Yamoto Town and the Tsukidate
district are administrative districts where the mostinjuries occurred in each stricken area. The injured inonly the Tsukidate district amounts to just 50% of the
injured in Iwate and Miyagi Prefectures during the2008 Iwate-Miyagi Inland Earthquake. The injured in
Yamoto Town reached approximately 62% of the total
during the 2003 Northern Miyagi Earthquake. The
data of Yamoto and Tsukidate are used as typical data
during each earthquake.
An absolute quantity of the injury rate depends
on the scale and the place. Therefore, the normalized
injury ratio calculated by dividing the injury rate inevery age class by the middle-aged class is proposedby the authors. The normalized injury ratio means
vulnerability to injury caused by earthquakes according to the age class. The calculated results are shownin Fig. 6. The proposed values as round numbers areshown with dotted lines in the figure. The concretevalues proposed by the authors are as follows. The
normalized injury ratio in the young-age class is halfthat of the middle-age class. The injury ratio in theold-age class is two and a half times the level of the
middle-age class. In the case of replacing the classification of every decade in age by Ohta and Ohashi(1986) during the 1978 Off Miyagi Earthquake withthree age classes of young, middle, and old, a similar
result to the normalized injury ratio in Fig. 6 is confirmed. Therefore, it was assumed that the proposedvalue could be applied to the periodic Off Miyagi
earthquakes in the subduction zone, even if the resultof Fig. 6 is based on inland earthquakes.

3.1 Evaluation of the injury rate in a few of thelatest earthquakes
To estimate the occurrence of injury caused by
the expected Off Miyagi earthquake, the change inthe population structure should be reflected in theestimation. Consequentially, data not only on the total
number of injured but data on injury according to age
class is also necessary. Here, the data on the numberof injured by age in the two latest earthquake disasters are used as an important reference. An outlineof the disaster during the July 26th, 2003 Northern
Miyagi Earthquake (2003 Northern Miyagi Earthquake) and the June 14th, 2008 Iwate-Miyagi Inland
Earthquake (2008 Iwate-Miyagi Inland Earthquake) isshown in Tab. 1. The two are both classified as inland
earthquakes. The maximum seismic intensity is also
the same. There is a difference in the stricken area
between plains and mountains. The major damage
modes during the 2003 Northern Miyagi Earthquake
were physical damage and human injury caused by
the earthquake shaking structures. The 2008 IwateMiyagi Inland Earthquake caused a large-scale landslide.
Data on human injury were published by the prefectural disaster headquarters. Major data include thenumber of fatalities and either the slightly or the seriously injured. Effective information for reflecting thedisaster lessons regarding human injury failed to berecorded. This is a common occurrence in the confusion of an earthquake disaster. Even if disaster medical scientists collect data on the injured, the focus
of interest is actual emergency medical care. Usefuldata for the prevention of injury are not necessarily
included. An investigation sheet of the injured wasmade based on collaboration between disaster medical science and natural disaster science to collect useful data for not only emergency medical care but alsoprior prevention. In spite of the delicate and private
information, various valuable attributes including age
were intentionally collected by the collaboration.
The injury rate according to age class basedon the data of Yamoto Town by the Ishinomaki Fire
Department during the 2003 Northern Miyagi Earthquake is shown as the white circle in Fig. 5 (Sato etal., 2006). The injury rate is defined as the percentageof those injured to every age group of the popula5

T. SATO, M. OBA, Y. SHINOZAWA, A. MANO, M. MOTOSAKA

Table 1. Outline of the latest earthquake disasters in Miyagi Prefecture
2003 Northern Miyagi
Prefecture Earthquake

2008 Iwate-Miyagi
Inland Earthquake

Occurrence time*1

7:13 on 26 July, 2003

8:43 on 14 June, 2008

Location of epicenter

38.40°N, 141.17°E

39.03°N, 140.88°E

Depth (km)128Magnitude*2

6.4

7.2

Maximum seismic intensity*2

Upper 6Upper 6

Number of fatalities

0*3

14*4

Number of those missing

0*3

4*4

Number of those injured

675*3

365*4

1,276*3

28*4

32*3

109*4

Number of collapsed houses
Amount of damage (billion yen)

*1 Japan standard time
*2 Definition by the Japan Meteorological Agency*3 Final release by Miyagi Prefectural Disaster Headquarters*4 Release by Miyagi Prefectural Disaster Headquarters on September 1st, 2009

Fig. 5 Injury rate by age class

Fig. 6 Normalized injury ratio by age class

3.2 Evaluation of the injured in Rokugo during the
Off Miyagi Earthquake in 1978
Those injured by the Off Miyagi Earthquake
in 1978 in Sendai City numbered 6,256. In Rokugo,
the number of those injured was 480 out of the6,256 (Sendai City, 1979). But there are no open
data regarding those injured with detailed attributes.
Therefore, the number of injured according to age
class during the Off Miyagi Earthquake in 1978 isestimated by applying the proposed normalized injury
ratio. There is also the precondition that the injury
rate of the middle-age class in expected Off Miyagi
earthquakes is assumed to be same as in the Off Miyagi Earthquake in 1978. The population in Rokugo
according to age class is set up to evaluate the numberof injured during the Off Miyagi Earthquake in 1978.

Change of the population in Rokugo according to age
class in the 30 years from 1975 is shown in Tab. 2.
The aging rate has changed remarkably from 5% to17%. The old-age population has increased approximately seven times in the past 30 years.
The breakdown number of the injured being
480 in 1978 is evaluated by applying the normalized
injury rate of 0.5, 1, and 2.5 for the young-age class,
middle-age class, and old-age class, respectively. The
estimated results of the injured in Rokugo in each age
class during the Off Miyagi Earthquake in 1978 areshown in Tab. 3. The number of injured in the oldage class is the same as in the young-age class in spite
the population of the old-age class being one-fifth thesize. The injured in the old-age class amounts to approximately 14% of the total injured.
6

INJURY ESTIMATION FOR FORESEEN EARTHQUAKES IN AN AGING SOCIETY AND ITS APPLICATION TO SENDAI CITY, JAPAN

Table 2. Change of the population in Rokugo in the age class over 30 years

1975
1978
2005

Number of population
Percentage
Number of population
Number of population
Percentage

Young(0 〜 14)3,286
26.2
4,319*
3,953
15.0

Middle(15 〜 64)
8,600
68.6
11,310*17,90467.9

Old(65 〜 )
650
5.2
857*
4,510
17.1

Total
12,536100.0
16,48626,367100.0* Estimated number by applying the ratio of each class divided by the total in 1975 to the population in 1978
Table 3. Evaluation of those injured in Rokugo according to age class during the Off Miyagi Earthquake in 1978

Number of the injured (A)Population (B)B / A (×100%)Young(0 〜 14)
66
4,319
1.53

3.3 Injury estimation in Rokugo against the expected
Off Miyagi earthquake
The occurrence time of the expected Off Miyagi
earthquake is assumed to be 2005. The year 2005 wasadopted as the assumed occurrence year of the earthquake because the fiscal year of the newest data thatwere already published as population statistics of thecensus was 2005 at this submission. The number of
those injured in Rokugo in the assumed event in 2005 isestimated considering the increase in population and theprogress of the aging of society. With the above factors
expected, the same condition in 1978 is applied to 2005.
The injury rate in the middle-age class and the normalized injury ratio are assumed to be a numerical valuethat can be applied regardless of the occurrence time ofthe expected event. The estimated results of the injuredin Rokugo according to age class are shown Tab. 4.
Under the estimation, the normalized injury ratio wasapplied as the most important condition. The number of
injured doubled in 27 years. In addition, the number inthe old-age class, 338, is five times greater than in 1978,
which was 66. The great influence of the aging society
is suggested regarding those injured by earthquakes.

Middle(15 〜 64)
348
11,3103.08

Old(65 〜 )
66
857
7.70

Total
480
16,486
2.91

3.4 Evaluation of the emergency response load ofcaring for the injured elderly
The emergency response load (ERL) of middleage people of caring for the injured elderly is defined
as follows. The ERL is newly proposed by the authors. It means the necessary number of middle-age
people to take care of injured old-age people as an
emergency response by voluntary disaster prevention
organizations in the neighborhood. The evaluated results are shown in Tab. 5.
ERL=IOA / (PMA – IMA)IOA: Number of injured in the old-age class
IMA: Number of injured in the middle-age class
PMA: Population of the middle-age class
From the results, injured elderly people could becared for by 166 people of middle age during the Off
Miyagi Earthquake in 1978. The load level has tripled
in the past 30 years. The influence of the increase in
the injured elderly has exceeded the effect of an increase in the middle-age population.

Table 4. Injury estimation according to age class in 2005 in Rokugo

Number of the injured (A)Population (B)B / A (×%)

Young
(0 〜 14)
59
3,953
1.49
7

Middle(15 〜 64)537
17,9043.00

Old(65 〜 )
338
4,510
7.49

Total
934
26,367
3.54

T. SATO, M. OBA, Y. SHINOZAWA, A. MANO, M. MOTOSAKA

Table 5. Evaluation of the emergency response load of taking care of the injured elderly
1978
2005

IOA
66
338

PMA
11,31017,904

4. DISCUSSION

IMA
348
537

ERL
1 / 166
1 / 51

injury and the sex of the injured person are also important factors. Therefore, human injury data should
be standardized to utilize valuable disaster lessons
learned from actual earthquakes with collaboration
between disaster medical science and natural disasterscience.
The proposed normalized injury ratio is the estimation result based on the inland earthquakes. Future tasks
are the examination of the applicable limit for oceanictype earthquakes like the Off Miyagi earthquakes.

Bold assumptions were used for injury estimation in the earthquakes, and furthermore, the variableof fatalities was excluded in this paper. But one of the
problems of earthquake disaster mitigation in an aging society was analyzed quantitatively. Not only the
number of the elderly injured but also the load levelof middle-age people of taking care of the injured
elderly has increased with the progress of aging ofsociety. The applicable limitation of the injury rate
and normalized injury ratio should be analyzed as afurther extraction. In Japan, the aging of society will
progress still more in the future. It is clear that the
total number of injured in the old-age class should be
reduced by preventive measures.
Emergency medical care workers would makeefforts to reduce the number of preventable deaths.
Positive efforts from the domain of natural disasterscience and earthquake engineering are expected toreduce the load of emergency medical care workers.
An important contribution from the domain is promoting the prevention of injury to people beforehand.
When medical science researchers investigate theactual situation of disaster medicine, effective factors
in the prevention of injury are not generally included.
Therefore, the inclusion of multiple factors in injury
estimation is necessary. The authors conducted an effective investigation during the Iwate-Miyagi Inland
Earthquake by interdisciplinary collaboration between
disaster medical science and natural disaster science.
Effective factors not only in medical preparedness but
also in prevention of injury were included in the survey specifications.
In addition, the relationship between cause andeffect should be formularized to estimate with highprecision which age class has been injured. The cause
is exposure to shaking as a seismic hazard. The effectis risk of injury. As for the same hazard, the risk increases when vulnerability is relatively high. Vulnerability is influenced by various factors. An importantfactor is the age of the injured person. The place of

5. CONCLUSIONS
The injury potential due to periodic Off Miyagi
earthquakes is influenced by the aging of society.
In this paper, three age classes are used as follows.
Young age is defined as the generation under 14 years.
Old age is defined as 65 years old or over. Middle age
is defined as the other group. The main conclusions
obtained are as follows.
(1) In Rokugo as the subject region in Sendai City,
the ratio of the old-age population divided by
the total population has increased three andhalf times in the past 30 years from the previous Off Miyagi Earthquake in 1978.
(2) The normalized injury ratio according to age
class was evaluated based on the latest earthquake disaster. The ratio in the old-age class is
two and half times that in the middle-age class.
(3) The number of injured in Rokugo in each age
class during the Off Miyagi Earthquake in 1978
was evaluated.
(4) Under the assumed occurrence of the expected
Off Miyagi earthquake in 2005, the number of
injured in Rokugo according to age class wasestimated considering an increase in populationand the progress of aging of society. The number of injured has increased five times in thepast 30 years.
(5) The emergency load response of taking care of
injured elderly people was evaluated. The loadof the middle-age group has increased approxi8

INJURY ESTIMATION FOR FORESEEN EARTHQUAKES IN AN AGING SOCIETY AND ITS APPLICATION TO SENDAI CITY, JAPANmately three times in the past 30 years.

Estimation of Earthquake Fatalities Rescue Activity
Management.” Proceedings of the Eighth Japan Earth-

ACKNOWLEDGMENTS

quake Engineering Symposium, 2205-2210 (in Japanese with an English abstract).

We thank the members of the Technical Working
Group of the Injuries Investigation Committee during
2008 Iwate-Miyagi Inland Earthquake for helpful discussions. The committee was composed of the Liaison
Conference of the Tohoku branch of the Architectural
Institute of Japan, Miyagi Medical Association, theMedical Preparation Section of the Miyagi Prefectural
Government, the Disaster Medical Science Section of
the Miyagikenoki Earthquake Disaster Prevention Research Committee, and the Disaster Control ResearchCenter in Tokoku University.
We are also grateful to Ishinomaki Fire Department for providing statistical data of the 2003 Northern Miyagi Earthquake used in this study. Finally, we
thank the following organizations for their support in
executing our investigation. The organizations are theMedical Section of the Kurihara City Government,
Ohsaki Citizens’ Hospital, and Furukawa Seiryo Hospital.

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