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R E S E A R C H A R T I C L E Open Access
Prevalence of mental disorders in migrants
compared with original residents and local
residents in Ningxia, China
Zhizhong Wang
1,3*
, Liqun Wang
1
, Jinyun Jing
1
and Chunping Hu
2
Abstract
Background: Ecological migrants has a special background compared with other types of migrant. However, the
mental health status of ecological migrants who were expected to benefit from a massive “ecological migration
project”initiated by the Chinese government is unknown. This study aims to explore the influence of environmental
change on individuals’mental health and to improve current understanding of the mechanisms that mental disorders
occurred.
Methods: The data were extracted from a cross-sectional study. Anxiety disorders, mood disorders and substance use
disorders were assessed using the Chinese version WHO-CIDI. The prevalence of mental disorders was stratified by
migration status into ecological migrant, local resident and original resident groups. Unconditional logistic regression
models were used to calculate the risk of prevalence among these three groups.
Results: After controlling for gender, ethnicity, age, marriage, and education, the migrants had lower risk of mental
disorders than original residents [OR = 0.70 (95 % CI: 0.57–0.86)], p< 0.001), but had a higher risk of mental disorders
than local residents [OR = 1.29 (95 % CI: 1.06–1.55)], p=0.007).
Conclusion: The ecological migration project may be beneficial to people’s mental health by improving their living
environment and social economy.
Keywords: Ecological migrants, Mental disorders, Epidemiology, Mainland China
Background
The migration experience can be difficult at best. Migrants
are exposed to a variety of difficult situations in the
destination country [1, 2]. Additionally, migrants may
have had traumatic experiences in their places of origin,
as some are refugees from warzones, international laborers
or individuals in exile [3]. Most studies have shown
that the migration experience can increase the risk of
psychiatric disturbances over both the short and the
long term [4]. For example, greater psychological dis-
tress and psychiatric morbidity have consistently been
found among migrants from the former Soviet Union
compared to Israel-born natives [5, 6]. These negative
influences can persist for generations [7, 8]. Some studies
have indicated that the influences of migration on mental
health depends on the motivations of migration. For ex-
ample, people who immigrate to unite family members
have been shown to have fewer mental disorders than ref-
ugees who are forced to leave their countries because of
war, severe weather or natural disasters [9].
In general, migration refers to the process of leaving
one’s country to live in another, and the word migrant
refers to those persons. Hundreds of thousands of studies
have focused on migrants who left their homes in one
country and traveled to another to take up residence. Only
a few studies, however, have focused on migrants who
relocated within the same country, such as rural-urban
migrant workers [10], ecological migrants (ecomigrants),
and project migrants [11] (such as the Three Gorges Dam
Project, the world’s largest hydroelectric dam built in 1994
which flooded or partially flooded thirteen cities, and
* Correspondence: wzhzh_lion@126.com
1
Department of Epidemiology and Statistic, School of Public Health, Ningxia
Medical University, Yinchuan 750004, China
3
1160#, Shengli Street, Yinchuan 750004, China
Full list of author information is available at the end of the article
© The Author(s). 2016 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Wang et al. BMC Psychiatry (2016) 16:366
DOI 10.1186/s12888-016-1088-y
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
forced millions of residents to leave their hometowns in
areas submerged by the reservoir). Ecological migration is
caused by environmental deterioration (e.g., desertification
and drought) that forces people to leave their homes; once
relocated, these persons must adjust their lifestyles to
those of the local population [12]. There are approxi-
mately 25 million ecomigrants in the world, taking into
account both international and internal migration. In
Bangladesh, an estimated 12 million to 17 million people
have fled their homes in recent decades because of envir-
onmental disasters –those living in low-elevation areas
are likely to experience more intense flooding in the fu-
ture, forcing them to leave their homelands. In several
countries in Africa’s Sahel region, which borders the
Sahara, approximately 10 million people have been driven
to move because of droughts and famines [13]. Compared
with traditional migrants, ecological migrants in Ningxia
have a unique history, culture, and religious background
[14]. The province of Ningxia is located in western China,
and over one-third of the population is Hui ethnicities.
The Hui ethnic minority group is largely descended
from those who came to China from Saudi Arabia seek-
ing work. Consequently, this ethnic group is composed
almost entirely of Muslims [15, 16]. In the 1990s, the
government began to help residents in southern moun-
tainous areas (in which seven counties were identified
as project counties by the Ningxia Development and
Reform Commission) resettle in the northern plain re-
gion of Ningxia. As of 2011, a total of 630,000 residents
who amount to approximately 30 % of the total popula-
tion of the project counties were involved in the migration
projects in Ningxia [17].
The field of migrant epidemiology examines the as-
sociation of migration with the rate of disease occur-
rence [18]. Studies of this type can help clarify whether
a disease of unknown causes is principally determined
by genetic inheritance or by environmental exposure.
For example, migration from a high-risk population to
a low-risk population should not affect the occurrence
of a genetically determined disease among migrants. In
contrast, migration from a high-risk population to a
low-risk population is expected to be associated with a
reduction in the occurrence of an environmentally de-
termined disease.
The current study aimed to examine the risk of mental
disorders in ecological migrants compared with local
residents and original residents to explore the associ-
ation of migration with mental disorders; and to im-
prove the current understanding of the mechanisms
that mental disorders occurred. We hypothesized that
ecological migrants, who were expected to benefit from
the massive “ecological migration project”initiated by
theChinesegovernment,hadalowerriskofmental
disorders than that of original residents.
Methods
Data sources
Thedataanalyzedinthisstudywereobtainedfrom
Epidemiological Survey of Mental Disorders in Ningxia
(ESMD-NX). The sampling process has been described
elsewhere [19]. First, 62 primary sampling units (PSUs)
were selected from 2,602 primary units (include 2209
villages and 393 neighborhood communities) using a
probability proportional to size method. Second, depend-
ing on the total number of households in the selected
PSUs, 60 to 210 households were systematically identified
from each PSU, yielding 6,890 selected households. Third,
interviewers visited each household and used the Kish se-
lection table to identify one eligible participant from each
household based on the inclusion criteria (aged 18 years
or older and a resident at the current address for at least 6
months) and the exclusion criteria (unconsciousness
caused by brain injury, brain tumor and/or craniotomy or
dementia; being in the acute phase of a cerebrovascular
accident; experiencing a severe illness that prevents
communication; having any obvious cognitive disabilities;
or currently suffering from deafness, aphasia or other
language barriers). A total of 414 households were ex-
cluded because a participant could not be located dur-
ing the study period, resulting in a sample of 6,476
residents participated in the interview. Those with
missing data were excluded, yielding a total of 5,811
participants (89.7 %) who completed the full interview
used for further analysis.
This analysis includes 4,366 participants. Of these,
1,726 were ecological migrants, 1,458 were local resi-
dents (those who lived in the northern plain region lo-
cated along the Yellow River, which is more developed
than the southern mountainous areas of Ningxia, with
per capita gross domestic production (GDP) over 5,000
US dollars in 2012 and offers convenient transportation
and a better living environment), and 1,182 were original
residents (indigenous people who have long lived in the
southern ecologically fragile mountainous areas, where
receive scant rainfall, have poorly nourished land and
with per capita GDP was less than 1,500 US dollars in
2012). We identified ecological migrants through the fol-
lowing questions: “How many times have you moved to
a totally new village?”If the response was “one or more
times,”they were asked two more questions: “Did you
move to this village because of the government’s Eco-
logical Migration Project?”and “How many years have
you lived in this village?”We defined the ecological mi-
grant group as those who had moved, were involved in
the Ecological Migration Project, and had lived at their
current address for at least 2 years. Participants sampled
from the project counties and lived in rural areas were
defined as the original residents group. Participants who
sampled from counties located in the plain region of
Wang et al. BMC Psychiatry (2016) 16:366 Page 2 of 6
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Ningxia (where the ecological migrants were resettled)
and lived in rural areas were defined as the local group.
Measurements
In-person CAPI [20] was conducted by trained lay medical
college students from July 2011 to January 2013. The
12-month prevalence of anxiety disorders (including
agoraphobia, generalized anxiety disorder, obsessive-
compulsive disorder, panic disorder, social phobia, specific
phobia, and neurasthenia), mood disorders (including
unipolar depressive disorder and bipolar disorder), and
substance use disorders (including alcohol use disor-
ders and tobacco dependence) were determined. The
WHO Composite International Diagnostic Interview
(WHO-CIDI) [21] was used to diagnose mental disor-
ders according to the ICD-10 diagnostic criteria. “Any
mental disorder”was defined as those who had experi-
enced at least one of the mental disorders mentioned
above.
Sociodemographic information was collected using the
demographic section of the WHO-CIDI, including age,
gender, education, marital status, ethnicity (Han vs. Hui),
and history of migration from other areas of the province
(yes vs. no). Physical health variables included self-reported
type II diabetes (yes vs. no) and hypertension (yes vs. no).
Data analysis
The analyses were performed using Statistical Analysis
System (SAS) software version 8.2 (SAS Institute Inc.,
Durham NC, USA.). The prevalence of anxiety disorders,
mood disorders and substance use disorders was strati-
fied by migration status into ecomigrant, local resident
and original resident groups. Post-stratification adjust-
ment weight was applied when estimating the prevalence
among three groups, and gender (male and female), age
(<30, 30–40, 40–50, 50–60, and over) and ethnicity (Hui
and Han) were used in constructing the post-stratification
adjustment according to the Sixth Census of Ningxia
2010. The Rao-Scott chi-square test was used to assess dif-
ferences in weighted prevalence among three groups [22].
Differences in sociodemographic characteristics and phys-
ical health variables among migrants, local residents, and
original residents were examined using one-way analysis
of variance (ANOVA) for continuous variables and
chi-square test for categorical variables. Four separate
non-conditional logistic regression models were cre-
ated to estimate the risk of mental disorders across
the three groups for different mental disorders under
controlling for demographic variables. Two dummy
variables were created to specify the groups being
compared (group_a : 1 = local residents, 0 = migrants +
original residents; group_b : 1 = original residents, 0 =
migrants + local residents). Odds ratios, along with their
95 % confidence intervals, were calculated for all models.
Given the exploratory nature of these analyses, the statis-
tical significance level was set at 0.05.
Results
Demographic characteristics of the participants
As shown in Table 1, the participants’demographic
characteristics varied across the three groups. The average
age of the migrants was significantly younger than that of
the local and original residents (P< 0.001). The proportion
of women in the migrant group was higher than that in
other groups (P< 0.001). Additionally, the migrant group
had a higher proportion of Hui individuals.
The comparison of the twelve-month prevalence of
mental disorders among the three groups
In Table 2, the original residents with higher prevalence
of mental disorders (15.9 %) than migrants (13.6 %) and
local residents (10.3), P< 0.001. Similar results for the
anxiety disorder. Meanwhile, the migrant had higher
prevalence of mood disorder than original residents and
local residents.
Table 1 Demographic characteristics of the participants
Variables Migrant
N= 1726
Local
N= 1458
Original
N= 1182
F/x
2
P
Age (year, mean, SD) 39 (15) 47 (14) 44 (15) 111.27 <0.001
Education (year, mean, SD) 4.5 (4.3) 5.2 (4.1) 5.2 (5.1) 13.05 <0.001
Gender (male,%) 38.9 42.4 47.5 21.30 <0.001
Ethnicity (Hui,%) 57.0 26.3 48.6 313.8 <0.001
Marriage (%)
married 87.6 90.6 89.0 61.49 <0.001
divorced or widowed 2.5 5.5 2.9
unmarried 9.8 3.8 8.1
Current smoking (%) 14.3 23.2 24.0 55.17 <0.001
Diabetes mellitus (%) 1.3 2.6 1.8 6.89 0.032
Hypertension (%) 8.6 15.0 13.1 32.57 <0.001
Table 2 The prevalence of mental disorders among migrants, local residents and original residents, % (weighted prevalence)
Variables Migrant N= 1726 Local N= 1458 Original N= 1182 x
2
P
Any mental disorder 15.3 (13.6) 10.5 (10.3) 16.3 (15.9) 22.07 <0.001
Anxiety disorder 11.8 (10.0) 7.4 (7.0) 12.2 (11.7) 9.46 0.008
Mood disorder 2.7 (2.7) 1.2 (0.9) 2.4 (2.4) 21.38 <0.001
Substance use disorder 0.6 (0.9) 1.2 (1.3) 1.4 (1.6) 3.22 0.199
Wang et al. BMC Psychiatry (2016) 16:366 Page 3 of 6
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Multivariable analysis
As shown in Table 3, controlling for demographical vari-
ables and physical health variables, migrants had a higher
risk of any mental disorders than local residents, which
also was true for anxiety and mood disorders. And mi-
grants with a lower risk of any mental disorders, as well as
of anxiety disorders, than original residents. Additionally,
no significant differences in the risk of substance use dis-
orders were found among the three groups.
Discussion
Over the past few decades, migration has become policy
in some areas of developing countries. Moreover, migra-
tion is an important health issue, as changes in the phys-
ical and social environment may associated with disease
patterns [23–25]. With the support (include family based
housing, community based road repairing and develop-
ing public transport) of the Ningxia government, people
living in adverse ecological areas and those living in poor
counties (districts) have relocated with family to better
living conditions. Original residents lived in the less de-
veloped mountainous areas, while local residents lived in
the well-developed plain area of Ningxia.
This study found that the risk of mental disorders
significantly differed among migrants, local residents,
and original residents. One possible reason is that the
migration is often motivated by economic, education,
age, gender, among other characteristics. Additionally,
genderandethnicitymayberiskfactorsforanymental
disorders and anxiety. Local residents have higher so-
cioeconomic status than original residents, which may
benefit migrants. Ecological migrants were significantly
younger than both local residents and original residents,
with a higher proportion of females. Those demographic
differences may contribute to the lower prevalence of
mental disorders among migrants compared with original
residents. The present study found when controlling for
demographics, migrants were consistently less likely to
have mental disorders than original residents, but they
were at a higher risk of mental disorders than local resi-
dents. The finding is consistent with previous studies [26].
Ecological migration is often perceived as a means to a
better end, i.e., to lifting oneself and one’s family out of
poverty and improving one’s standard of living [27]. In-
come level may affect physical conditions, and a high in-
comemayhaveapositiveassociationwithmentalhealth.It
should be noted that economic, educational and social sup-
port are accessible to ecological migrants in China. Mi-
grants may have experienced better mental health in
this study because of the improvements in their living
conditions and the financial support provided by the
Chinese government (include offer allowance, reduce
tax, and living skills training), but these benefits do not
eliminate the potentially negative influences of previous
Table 3 Odds ratios estimated by logistic regression
Variables B (SE) Pvalue aOR (95 % CI)
Any mental disorder (N= 4366)
age 0.02 (0.04) 0.677 1.02 (0.94,1.10)
gender 0.22 (0.09) 0.017 1.25 (1.04,1.51)
ethnicity 0.37 (0.09) <0.001 1.44 (1.20,1.74)
education −0.02 (0.01) 0.045 0.98 (0.95,1.00)
divorced/widowed −0.12 (0.25) 0.638 0.89 (0.55,1.45)
unmarried 0.25 (0.19) 0.175 1.29 (0.89,1.86)
Diabetes mellitus 0.11 (0.30) 0.713 1.12 (0.61,2.03)
hypertension 0.18 (0.14) 0.202 1.20 (0.91,1.58)
local residents −0.35 (0.10) <0.001 0.70 (0.57,0.86)
original residents 0.25 (0.09) 0.007 1.29 (1.06,1.55)
Anxiety (N= 4366)
age 0.05 (0.04) 0.223 1.05 (0.97,1.15)
gender 0.59 (0.11) <0.001 1.81 (1.45,2.26)
ethnicity 0.45 (0.11) <0.001 1.57 (1.27,1.94)
education −0.03 (0.01) 0.012 0.97 (0.94,0.99)
divorced/widowed −0.16 (0.27) 0.552 0.85 (0.49,1.46)
unmarried 0.44 (0.21) 0.041 1.55 (1.02,2.37)
Diabetes mellitus 0.19 (0.33) 0.552 1.22 (0.64,2.31)
hypertension 0.21 (0.16) 0.186 1.23 (0.90,1.67)
local residents −0.41 (0.12) <0.001 0.66 (0.52,0.83)
original residents 0.26 (0.10) 0.014 1.30 (1.05,1.61)
Mood disorders (N= 4366)
age 0.13 (0.09) 0.148 1.14 (0.95,1.36)
gender 0.25 (0.23) 0.277 1.28 (0.82,2.00)
ethnicity 0.17 (0.22) 0.451 1.18 (0.76,1.83)
education −0.01 (0.03) 0.891 0.99 (0.94,1.05)
divorced/widowed 0.58 (0.46) 0.211 1.78 (0.72,4.40)
unmarried 0.35 (0.43) 0.405 1.43 (0.62,3.29)
Diabetes mellitus
a
−13.98 (765.2) 0.985 -
hypertension −0.21 (0.36) 0.561 0.81 (0.40,1.64)
local residents −0.84 (0.28) 0.002 0.43 (0.24,0.74)
original residents 0.18 (0.22) 0.672 1.20 (0.77,1.88)
Substance use disorders (N= 4364)
age −019 (0.13) 0.142 083 (0.64,1.07)
gender
a
−14.64 (184.30) 0.937 -
ethnicity −0.70 (0.34) 0.040 0.49 (0.25,0.97)
education 0.01 (0.04) 0.762 1.01 (0.94,1.09)
divorced/widowed
a
−12.50 (533.20) 0.981 -
unmarried
a
−14.22 (430.20) 0.974 -
Diabetes mellitus 1.45 (0.66) 0.028 4.25 (1.17,15.45)
Hypertension −0.18 (0.51) 0.721 0.83 (0.30,2.28)
local residents 0.07 (0.31) 0.824 1.07 (0.57,2.00)
original residents 0.36 (0.31) 0.245 1.44 (0.77,2.66)
a
No proper ORs were calculated because very few positive cases report
substance use disorders in one of the group
SE standard error, OR odds ratio, 95 % CI 95 % confidence interval,
aOR adjusted odds ratia
Wang et al. BMC Psychiatry (2016) 16:366 Page 4 of 6
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experiences in their original homes on mental health.
Previous studies have shown that workers who migrate
from rural to urban settings in China are not particu-
larly vulnerable to poor mental health. This may be be-
cause of the sense of well-being that is associated with
upward economic mobility and improved opportunities
or because of the relatively high social capital found in
migrant communities [28]. This finding is consistent
with research conducted outside of China as well. For
example, Patel reviewed 11 community-based studies and
found that most of them reported an association between
indicators of poverty and the risk of mental disorders [29].
Similarly, Nandi et al. found a dramatic decrease in anxiety
disorders among those with improved living conditions in a
20-year cohort study [30].
The Ecological Migration Project has been a key envir-
onmental policy in which thousands of people have par-
ticipated, especially in the northern areas of China. This
study is the first to explore the association of migration
with the mental health in ecomigrants. These findings
may further the current understanding of how environ-
mental and genetic factors influence the development of
mental disorders.
This study has several limitations. First, given its
cross-sectional design, this study cannot identify causal
relationships between migration and the mental disorders.
Second, this study does not examine the relationship be-
tween mental disorders and participants’decisions or mo-
tivations to migrate from their homes and, thus, from
their social resources. There were few positive cases for
every single specific disorders, the present study failure to
evaluate the influence of migration on the specific mental
disorders. Prospective data will be needed to help identify
the causal factors that influence the development of men-
tal disorders in this population.
Conclusions
This study showed that after adjust the influence of gen-
der, ethnic, age and other factors, the migrants more
likely had mental disorders than local residents, and had
a lower prevalence than original residents. The findings
indicate that ecological migration project in Ningxia area
did not increase the burden of mental disorders of the im-
migrant population, due to the cross-sectional design, fur-
ther prospective studies needed to verify the conclusions.
Abbreviations
CAPI: Computer-assisted personal interview; GDP: Gross domestic production;
PSU: Primary sampling units; WHO-CIDI: World health organization composite
international diagnostic interview
Acknowledgments
The authors would like to thank the Ningxia CDC for its assistance during
data collection and the Peking University Institute of Mental Health for providing
the training materials. We would also like to thank Harold G. Koenig for editing
the text.
Funding
This study was funded by the National Natural Science Foundation of China
(81060242). The funder had no role in designing the study; collecting,
analyzing or interpreting the data; writing the manuscript; or deciding
submit the paper for publication.
Availability of data and materials
The dataset supporting the conclusions of this article is included within the
article. Additional data are available from the Epidemiological Survey of
Mental Disorders in Ningxia, data supporting our findings will be shared on
individual request at wzhzh_lion@126.com.
Authors’contributions
WZ participated in the design of the study, conducted the data collection,
and wrote the first draft of the manuscript. WL participated in the design of
the study, conducted the statistical analysis and helped draft the manuscript.
JJ provided summaries of previous research studies and edited the text. HC
conducted the data analysis and reviewed the draft manuscript. All authors
read and approved the final manuscript.
Competing interests
The authors declare that they have no competing interets.
Consent for publication
Not applicable.
Ethics approval and consent to participate
This study was approved by the Institutional Review Board of the Ningxia
Medical University (document number: 2014–176). A consent form was included
in the computer-assisted personal interview (CAPI) program. Before conducting
the interview, the interviewer logged into the system, read the potential risks
and benefits of the survey, and asked the participants to provide their consent
by checking a box on the computer screen to provide their response (either 1 = I
agree to participate in the study or 5 =I do not agree to participate in the study).
If the response was “I do not agree,”the CAPI program was automatically and
immediately terminated. Each participant’sconsentwasrecordedasavariablein
the dataset file by the computer program.
Author details
1
Department of Epidemiology and Statistic, School of Public Health, Ningxia
Medical University, Yinchuan 750004, China.
2
Department of Psychiatry,
Minkang Psychiatric Hospital of Civil Affairs, Ningxia, Yinchuan 750010, China.
3
1160#, Shengli Street, Yinchuan 750004, China.
Received: 19 May 2016 Accepted: 24 October 2016
References
1. Fossion P, Servais L, Rejas MC, Ledoux Y, Pelc I, et al. Psychosis, migration
and social environment: an age- and-gender controlled study. European
Psychiatry. 2004;19(6):338–43.
2. Bhugra D. Migration and mental health. Acta Psychiatrica Scandinavica.
2004;109(4):243–58.
3. Bhui K, Abdi A, Abdi M, Pereira S, Dualeh M, et al. Traumatic events,
migration characteristics and psychiatric symptoms among Somali refugees.
Soc Psychiatry Psychiatr Epidemiol. 2003;38(1):35–43.
4. Norredam M, Garcia-Lopez A, Keiding N, Krasnik A. Risk of mental disorders
in refugees and native Danes: a register-based retrospective cohort study.
Soc Psychiatry Psychiatr Epidemiol. 2009;44(12):1023–9.
5. Mirsky J. Mental health implications of migration: a review of mental health
community studies on Russian-speaking immigrants in Israel. Soc Psychiatry
Psychiatr Epidemiol. 2009;44(3):179–87.
6. Ponizovsky AM, Ritsner MS, Modai I. Suicidal ideation and suicide attempts
among immigrant adolescents from the former Soviet Union to Israel. J Am
Acad Child Adolesc Psychiatry. 1999;38(11):1433–41.
7. Fossion P, Ledoux Y, Valente F, Servais L, Staner L, et al. Psychiatric disorders
and social characteristics among second-generation Moroccan migrants in
Belgium: an age-and gender-controlled study conducted in a psychiatric
emergency department. European Psychiatry. 2002;17(8):443–50.
Wang et al. BMC Psychiatry (2016) 16:366 Page 5 of 6
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
8. Slonim-Nevo V, Sharaga Y. Psychological and social adjustment of
Russian-born and Israeli-born Jewish adolescents. Child Adolesc Soc Work
J. 2000;17(6):455–75.
9. Norredam M, Olsbjerg M, Petersen JH, Juel K, Krasnik A. Inequalities in
mortality among refugees and immigrants compared to native Danes–a
historical prospective cohort study. BMC Public Health. 2012;12:757.
10. Harpham T. Urbanization and mental health in developing countries: a
research role for social scientists, public health professionals and social
psychiatrists. Soc Sci Med. 1994;39(2):233–45.
11. Tan Y, Hugo G, Potter L. Government-organized distant resettlement and
the Three Gorges Project, China. Asia-Pac Popul J. 2003;18(3):1–26.
12. Nakawo, Masayoshi, Yuki. Ecological Migration: Environmental Policy in
China. In: Shinjilt, editor. New York: Peter Lang International Academic
Publishers; 2011. p. 12.
13. Washingtonpost. Climate Fears Are Driving ‘Ecomigration’Across Globe.
2009. http://www.washingtonpost.com/wp-dyn/content/article/2009/02/22/
AR2009022202378.html. Accessed 27 Oct 2015.
14. Zhang LX, Liu J. Key issues of ecological migration in northern deserted
areas of China. Chin J Ecol. 2009;28(7):1394–8.
15. Gladney D. Islam in China: Accommodation or Separatism? In: Overmyer DL,
editor. Religion in China Today. Cambridge: Cambridge University Press;
2003. p. 145–61.
16. Ho WY. Mobilizing the Muslim minority for China’s development: Hui
Muslims, ethnic relations and Sino-arab connections. J Comp Asian Dev.
2013;12:84–112.
17. Statistical Bureau of Ningxia. Ningxia Statistical Yearbook. Beijing: China
Statistics Press; 2012.
18. Greenberg RS. Medical Epidemiology. third editionth ed. USA: McGraw Hill
companies, Inc; 2002. p. 40.
19. Wang ZZ, Koenig HG, Zhang YH, Ma WR, Huang YQ. Religious involvement
and mental disorder in mainland China. PLoS ONE. 2015;10(6):e0128800.
20. Baker RP. New technology in survey research: Computer-assisted personal
interviewing (CAPI). Soc Sci Comput Rev. 1992;10:145–57.
21. Kessler RC, Üstün TB. The World Mental Health (WMH) Survey Initiative
version of the World Health Organization (WHO) Composite International
Diagnostic Interview (CIDI). Int J Methods Psychiatr Res. 2004;13:93–121.
22. Rao JNK, Scott AJ. On simple adjustments to chi-square tests with sample
survey data. Ann Stat. 1987;15(1):385–97.
23. Bhugra D. Cultural identities and cultural congruency: a new model for
evaluating mental distress in immigrants. Acta Psychiatr Scand. 2005;111:84–93.
24. Murphy HB. Migration, culture and mental health. Psychol Med. 1977;7:677–84.
25. Nicolas G, Desilva AM, Subrebost KL, Breland-Noble A, Gonzalez-Eastep D, et al.
Expression and treatment of depression among Haitian immigrant women in
the United States: clinical observations. Am J Psychother. 2007;61:83–98.
26. Lichtenstein P, Yip BH, Björk C, Pawitan Y, Cannon TD, et al. Common
genetic determinants of schizophrenia and bipolar disorder in Swedish
families: a population-based study. Lancet. 2009;373(9659):234–9.
27. Li PL, Wang XY. Ecological Migration, Development and Transformation: A
Study of Migration and Poverty Reduction in Ningxia. Heidelberg, New York,
Dordrecht, London: Springer; 2015.
28. Li L, Wang HM, Ye XJ, Jiang MM, Lou QY, et al. The mental health status of
Chinese rural–urban migrant workers. Soc Psychiatry Psychiatr Epidemiol.
2007;42(9):716–22.
29. Patel V, Kleinman A. Poverty and common mental disorders in developing
countries. Bull World Health Organ. 2003;81(8):609–15.
30. Nandi D, Banerjee G, Mukherjee SP, Ghosh A, Nandi PS, et al. Psychiatric
morbidity of a rural Indian community: changes over a 20-year interval. Br J
Psychiatry. 2000;176:351–6.
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