Damage, Living Environment, and Reconstruction under the Great East Japan Earthquake-The 6th Survey of Nuclear Disaster Evacuees from Futaba, Fukushima, Summary of Results 2020　　|ニッセイ基礎研究所

Damage, Living Environment, and Reconstruction under the Great East Japan Earthquake-The 6th Survey of Nuclear Disaster Evacuees from Futaba, Fukushima, Summary of Results 2020　

保険研究部准主任研究員岩﨑敬子

1――Basic Information

Surveys on damage, living environment and reconstruction under the Great East Japan Earthquake have been conducted by a research project, "International comparison of reconstruction of living infrastructure from disasters" (Yasuyuki Sawada, Professor, Faculty of Economics, The University of Tokyo; Keiko Iwasaki, Researcher, NLI Research Institute) of the University of Tokyo since 2013. The surveys are targeted to all household heads of Futaba in Fukushima prefecture, where all residents were forced to evacuate due to the nuclear power plant accident caused by the Great East Japan Earthquake ooccured in 2011. Surveys were conducted in July 2013, December 2014, July 2016, December 2017, July 2019 and December 2020. This paper reports the summary of results of the sixth survey conducted in December 2020.¹

The survey include questions about basic attributes such as age and sex, as well as quetions related to connections with others (social capital) and health conditions (See appendix at the end of this report for all the questions included in the survey). The questionnaires were distributed to all households of Futaba (About 2,900 households) that receive the regular town mail from Futaba. We also distributed simplified version of the questionnaires excluding already available information in previous rounds of surveys to those who had filled out names and addresses in previous surveys. We received responses from 789 Futaba residents who had evacuated nationwide (416 responses from questionnaires included in the town mail, 373 responses from the simplified version of the questionnaires. Response rate is about 27%).

Figures 1 and 2 show the distribution of age and sex of the respondents. As we can see from these figures, compared to the age and sex distribution reported in the national census, the age distribution of the respondents is left-skewed, with the majority of respondents in their late 60s. The sex distribution shows that the majority of respondents are male. In addition, since the survey was conducted after the tremendous disaster, it is possible that the distributions of the respondents' characteristics are significantly different from those of general questionnaire surveys. Therefore, it should be noted that the results of this survey do not necessarily indicate the general trend of Futaba residents.

Figure１．Age distribution of respondents/Figure 2.Sex distribution

¹ This research has been supported by the following research grants.
Grant-in-Aid for Scientific Research (15 J09313, 26220502, LZ003), Research Grants of the Japan Center for Economic Research.
This study is approved by the Ethics Committee of the University of Tokyo (20-244).

2――Health conditions

Regarding health condition of the respondents, as shown in Figure 3, many rated their own health condition before the earthquake as "good" or "very good" while many rated their current health status as "bad," "terrible" or "can't say either way". Compared to the 2016 survey result, the portion of respondents who rated their current health stasus as "good" increased in 2019 survey, while the portion of respondents who rated their current health status as "bad" decreased slightly, indicating that overall health status of Futaba residents have been gradually recovering. On the other hand, as shown in Figure 4, when asked about changes in health condition compared to pre-disaster status, many respondents rated their own health condition as worse than that of pre-disaster status and the distribution has hardly changed since 2013.

Figure 4. Change in subjective health status

As to mental health, the distribution of K6 score, a clinically varidated index for diagnosing the overall stress state, of Futaba residents gradually improved from 2013 to 2020 (See Figure 5). However, the scores are still higher than those in the other disaster affected areas, indicating that mental health recovery of Futaba may take a very long time. (K6 is an internationally used measurement for general mental health status that consists of six questions. The higher the total score, the more likely the respondent is stressed.)

Figure 5. Distribution of K6 score for Japan, Futaba,and other disaster affected areas

In addition, the previous rounds of surveys between 2013 and 2017 showed that K6 score among Futaba residents living in temporary shelters had been increasing year by year, but only few lived in temporary shelter among respondents of the 2019 and 2020 survey (6 respondents in 2019 and 7 respondents in 2020) since many who used to live in temporary shelters had moved to public reconstruction housings. Therefore, instead of checking the distribution of K6 score among temporary shelter residents, we compare the distribution of K6 score by dwelling type this time. As shown in Figure 6, K6 score among residents of public reconstruction housings tend to be higher than that of residents who live in owned houses. This suggests the importance of continuous mental health support even after leaving from temporary shelters.

Figure 6. Distribution of K6 by dwelling type

However, the results of this survey do not necessarily apply to all residents of Futaba, and high K6 score does not necessarily mean that one has a mental disorder. Please note that the purpose of our survey is to provide policy implications.

3――Change in social capital

Social capital refers to trusting relationships and networks, and is sometimes referred as "kizuna" in Japanese. Social capital is getting attention as a key notion to achieve successful disaster recovery and has been one of the major focuses of our study. In previous study, we showed social capital would play an important role in maintaining mental health after the disaster, while it might have been weakened by the disaster among Futaba residents.

There are several indicators that are commonly used to measure social capital, but we focus on three items here. First, we check the level of "generalized trust" using GSS trust question, which is one of the most commonly used social capital measures. As shown in Figure 7, generalized trust among Futaba residents had been decreasing from 2013 to 2016 (Portion of those who think people can be trusted had been decreasing). However, since 2017, the portion of those who thinks people can be trusted has been gradually increasing (See Figure 7). The overall distribution is almost same as that of Japan as of 2019. On the other hand, Since Futaba had very high generalized trust level before the disaster, recovery to its original high level would take much longer time.

The second indicator of social capital, "frequency of mutual assistance with neighbors," also shows a gradual recovery trend. In addition, the third indicator of social capital, "trust to neighbors" also shows a gradual recovery trend since 2016, but both trends have been very moderate. It will take a very long time for social capital to recover, and we believe it is important to continue to monitor these changes over the long term.

Figure 8. Frequency of mutual assistance with neighbors

4――Building relationship with residents at evacuation desitinations

Some of Futaba residents had told us that building a new social relationship with residents in evacuation destinations is an challenge that needs to be addressed under the prolonged evacuation period, in which the policies and understandings of residents in evacuation destinations vary widely. To capture this challenge, since the 2016 survey, the question on the relationship with the residents of the evacuation desitinations have been included. As shown in Figure 10, the percentage of those who feel that it is better to hide that they are from Futaba, those who feel uneasy about taking out garbage, and those who are called bad names or misbehaved because they are from Futaba have been decreasing. On the other hand, the percentage of residents who have opportunities to interact with the residents of the evacuation destinations, those who participate in events held in the evacuation destinations, and those who think it is better to conceal that they are from Futaba have not changed. It shows that about half of the residents wtill do not have opportunities to interact with residents of the evacuation destinations, indicating that building new relationships with residents at the evacuation destinations is still an important challenge for Futaba residents.

Figure 10. Relationship with residents in evacuation destinations

5――Summary of the findings from the five rounds of surveys

(1) Futaba residents can be facing more serious psychological distress than those in other disaster affected areas. More than eight years have passed since the Great East Japan Earthquake, and their mental health status have been gradually improving, but recovery may take much longer time.

(2) In particular, there was a possibility that mental health of those who had lived in temporary shelters for long time was in a serious condition. However, currently, even after many of the residents have already moved from temporary shelters to public reconstruction housings, mental health of residents in public reconstruction housings is in a serious condition, and continuous support is necessary.

(3) As to changes in income and health condition caused by the disaster, we find that the greater the extent of decrease or deterioration is, the greater the degree of decline in individual well-being tends to be. This implies the necessity of sufficient compensation to recover the original state of survivors’ well-being.

(4) The disaster has weakened social capital of Futaba residents, and recovery may take very long time.

(5) Keeping in touch with people who had been friends from pre-disaster time and participating in hobbies and volunteer activities after the disaster may help people maintain good mental health.

(6) Though relationship building with the residents of the evacuation destinations show some progress little by little, the progress is subtle and it is still an important challenge evacuees are facing.

(7) Aggravated present bias (procrastination tendency) due to disasters can lead a decline in mental health condition, but policies that promote interaction among residents and encourage good health behaviors can prevent such a decline.

These results have been presented in international and domestic academic conferences. Also, these results have been published in international academic journals. Furthermore, a book, Fukushima Nuclear Disaster and Mental Health was published from Nippon hyoron sha in March 2021. We intend to continue our analysis and contribute to improve disaster preparation/rehabilitation policies.

Participants of our surveys are approximately 27% of households of Futaba and the results do not represent all Futaba residents. Since the survey was conducted after a major disaster, the characteristics of respondents may be very different from general surveys and there is a possibility of an overestimation in deterioration of health condition in our results. Therefore, we need a special caution in interpreting the results, and any definitive judgments based solely on these findings should be avoided.

日付	タイトル	執筆者	媒体
2025/06/16	マスク着用のメンタルヘルスへの影響（１）－コロナ禍の研究を経て分かっていること/いないこと	岩﨑敬子	基礎研レター
2025/06/12	マスク着用の健康への影響－コロナ禍の研究を経て分かっていること/いないこと	岩﨑敬子	基礎研レポート
2023/03/28	子どもがマスクを外すことを嫌がる場面と頻度～感染拡大初期と2022年10月の比較	岩﨑敬子	基礎研レポート
2023/03/28	子どもがマスクを着用することを嫌がる場面と頻度～感染拡大初期と2022年10月の比較	岩﨑敬子	基礎研レポート

日付

タイトル

執筆者

媒体

2025/06/16

マスク着用のメンタルヘルスへの影響（１）－コロナ禍の研究を経て分かっていること/いないこと

岩﨑敬子

基礎研レター

2025/06/12

マスク着用の健康への影響－コロナ禍の研究を経て分かっていること/いないこと

岩﨑敬子

基礎研レポート