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ARTICLE DETAILS
TITLE (PROVISIONAL)
AUTHORS
Differences in predictors of permanent work disability between
immigrants and natives – a cohort study of adults with sick leave due
to common mental disorders
Werlen, Laura; Helgesson, Magnus; Mittendorfer-Rutz, Ellenor
VERSION 1 - REVIEW
REVIEWER
REVIEW RETURNED
Blanca Reneses
Institute of Psychiatry and Mental Health. Institute of Research
(IdISSC). San Carlos University Hospital.
Complutense University.
Madrid.
Spain
02-Dec-2016
GENERAL COMMENTS
The manuscript is well written, the objectives are clear and the
methodology correct. The results are adequately discussed and the
conclusions are accurate.
REVIEWER
Billy Gazard
King's College London, Psychological Medicine, Institute of
Psychiatry, Psychology and Neuroscience, 10 Cutcombe Road,
London, UK
03-Jan-2017
REVIEW RETURNED
GENERAL COMMENTS
This paper makes use of rich data from a complex data linkage in
order to investigate differences in the predictors of permanent work
disability in migrant and non-migrant groups who have had sick
leave due to common mental disorder. Overall, the paper is well
written and the paper‟s use of appropriate data sources to address
its aims make a novel and important contribution to the literature.
However, the study has been designed to investigate differences
between what the authors describe as „western‟ and non-western‟
immigrant groups which presents a number of problems that are not
fully addressed in the paper. My main concern is that there is no
justification for grouping migrants in such a way and that this division
may mask the real reason for differences such as „reason for
migration‟. As the authors states, the „non-Western‟ group consists
mainly of refugees and relatives seeking reunification. This sentence
also suggests that they have data on „reason for migration‟ that
could be incorporated into the analysis. The rest of the analysis is
sound, however, I would like to see this main concern addressed
before publication as well as some other specific suggestions as
outlined below:
1. Introduction
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Page4Line25-26; references 9-11 refer to studies in Sweden only.
Please make this clear or include international references (which are
more mixed in terms of the findings on this association).
Page4Line 52; the author states that pathways to permanent
disability may vary in migrant groups by country of birth/reason for
migration. Could you add a sentence on this giving more detail e.g.
which country of birth/reasons for migration and how? When
expanding on this I would like to see a justification for grouping
migrants as „Western‟ and „non-Western‟.
2. Methods
Page7Line14-16; The author states that „non-Western‟ migrants
consist mainly of refugees and relatives seeking reunification. Does
this mean that you have data on reason for migration? If so, why has
this not been incorporated into the analysis and presented in tables?
Given the higher risk of CMD symptoms in refugees I would like to
see this incorporated into the study design if possible.
3. Discussion
Page16Line41-43; You state that the differences in morbidity
measures could be interpreted as differences in symptom severity
but do not discuss why. What role does „reason for migration‟ play
here? Surely, one explanation could be due to the proportion of
refugees in this grouping?
Page17Line30-34; the sentence suggests that differences in the
culture of migrants as an explanation for differences in access to
labour markets etc. Another possible explanation in the research
literature is that migrants experience more discrimination in the
labour market (See Hatch, S. L., et al. "Discrimination and common
mental disorder among migrant and ethnic groups: findings from a
South East London Community sample." Social psychiatry and
psychiatric epidemiology 51.5 (2016): 689-701). What role does
discrimination based on ethnicity and first language add to this
relationship given the differences for „non-Western‟ migrants?
Page18Line23; Again, what about the role of discrimination and
responses to discrimination in this process (e.g. avoidance of health
services)
Page18Line32-34; Too little attention given to this limitation. You
have acknowledged the limitation but could this not be addressed by
using reason for migration as a variable in the analysis?
VERSION 1 – AUTHOR RESPONSE
1. Introduction
Page4Line25-26; references 9-11 refer to studies in Sweden only. Please make this clear or include
international references (which are more mixed in terms of the findings on this association).
A: We have clarified that the stated relationship refers to conditions in Sweden and Denmark (Page 4,
Line 25).
Page4 Line 52; the author states that pathways to permanent disability may vary in migrant groups by
country of birth/reason for migration. Could you add a sentence on this giving more detail e.g. which
country of birth/reasons for migration and how? When expanding on this I would like to see a
justification for grouping migrants as „Western‟ and „non-Western‟.
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A: Thank you for this comment. We have removed “reason for migration” to be more consistent with
the study aim (Page 4, Line 52). We have also added a sentence on differences between countries of
birth and subsequent pathways to disability pension (Page 4, Lines 52-57). The reason for dividing
immigrants in Western and non-Western immigrants was to highlight differences in the reasons for
migration. Western migrants mostly consist of voluntary immigrants, i.e. labour migrants while nonwestern immigrants are more likely to be refugees or kin to refugees who more or less have been
forced to leave their birth country due to war and conflicts.
2. Methods
Page7Line14-16; The author states that „non-Western‟ migrants consist mainly of refugees and
relatives seeking reunification. Does this mean that you have data on reason for migration? If so, why
has this not been incorporated into the analysis and presented in tables? Given the higher risk of
CMD symptoms in refugees I would like to see this incorporated into the study design if possible.
A: As the reviewer points out, there are a number of reasons to divide migrants regarding ground for
settlement. As we in our dataset unfortunately do not have data on ground for settlement, our
reasoning for dividing immigrants into Western and non-Western immigrants was to find a proxy for
ground for settlement. Based on statistics from Statistics Sweden one can see that refugees and
relatives seeking reunification build the outmost largest share of immigrants to Sweden from outside
the Western World. From Asia, 21,890 refugees, (mostly Syrian, 17,601 persons), 22,823 relatives
seeking reunification (much more divided into several countries) and 10,870 labour migrants (India
(3,443), Thailand (3,033), China (1,337) Syria (780), Iran (446), Pakistan (237) etc.) immigrated to
Sweden in 2014 according to Swedish Migration Agency. Labour migrants came mostly from. From
Africa, 8,811 refugees, 7,515 relatives seeking reunification and 516 labour migrants immigrated to
Sweden in 2014 (https://www.migrationsverket.se/English/About-the-Migration-Agency/Facts-andstatistics-/Statistics/Overview-and-time-series.html). We have now more clearly stated the reason for
dividing migrants into Western and Non-Western countries in the manuscript (Page 4, Lines 47-57,
Page 5, Lines 3-10). We have also stated more clearly that the division into Western and nonWestern immigrants might be prone to some limitations (Page 19, Lines 34-41). In the methods part,
this information was taken out in order to limit misunderstanding (Page 7, Lines 18-25).
3. Discussion
Page16Line41-43; You state that the differences in morbidity measures could be interpreted as
differences in symptom severity but do not discuss why. What role does „reason for migration‟ play
here? Surely, one explanation could be due to the proportion of refugees in this grouping?
A: We agree that one explanation could be the proportion of refugees in this group. Therefore, we
have added a sentence regarding refugees in this section (Page 17, Lines 41-43).
Page17Line30-34; the sentence suggests that differences in the culture of migrants as an explanation
for differences in access to labour markets etc. Another possible explanation in the research literature
is that migrants experience more discrimination in the labour market (See Hatch, S. L., et al.
"Discrimination and common mental disorder among migrant and ethnic groups: findings from a South
East London Community sample." Social psychiatry and psychiatric epidemiology 51.5 (2016): 689701). What role does discrimination based on ethnicity and first language add to this relationship
given the differences for „non-Western‟ migrants?
A: As the reviewer points out, discrimination might be an underlying reason for difficulties among
immigrants to enter the labour market. Studies report that problems on the labour market are greater
among migrants from countries where the cultural distance to the host country is wide and
discrimination may be a factor leading to these problems. We have added a sentence regarding the
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role of discrimination in the manuscript and added additional references – including the one
suggested (Page 18, Lines 34-36).
Page18Line23; Again, what about the role of discrimination and responses to discrimination in this
process (e.g. avoidance of health services)
A: We have added a sentence regarding discrimination also here, avoidance of health care may be
multifactorial and discrimination of different kinds might play a role (Page 19, Lines 25-27).
Page18Line32-34; Too little attention given to this limitation. You have acknowledged the limitation
but could this not be addressed by using reason for migration as a variable in the analysis?
A: We have now clarified as a limitation in the manuscript that we do not have data on ground for
settlement (Page 19, Lines 34-41).
Please revise your title so that it includes your study design. This is the preferred format for the
journal.
A: We have, in the title, stated that the study is a cohort-study (Page 1, Lines 3-5).
VERSION 2 – REVIEW
REVIEWER
REVIEW RETURNED
GENERAL COMMENTS
Billy Gazard
King's College London, UK
15-Feb-2017
The authors have addressed my concerns regarding the
categorization of migrant groups and have modified the manuscript
accordingly. Their additions to the paper have made the justification
for grouping migrants in the way that they did clear while also
addressing this as a limitation of the study.
Downloaded from http://bmjopen.bmj.com/ on June 16, 2017 - Published by group.bmj.com
Differences in predictors of permanent work
disability between immigrants and natives: a
cohort study of adults with sick leave due to
common mental disorders
Laura Werlen, Magnus Helgesson and Ellenor Mittendorfer-Rutz
BMJ Open 2017 7:
doi: 10.1136/bmjopen-2016-014431
Updated information and services can be found at:
http://bmjopen.bmj.com/content/7/3/e014431
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