Chemobrain Experienced by Breast Cancer Survivors: A
Meta-Ethnography Study Investigating Research and
Care Implications
Maryam Hafsah Selamat1, Siew Yim Loh2,3*, Lynette Mackenzie3, Janette Vardy4,5
1 Department of Postgraduate Studies, University of Malaya, Kuala Lumpur, Malaysia, 2 Department of Rehabilitation Medicine, Faculty of Medicine, University of Malaya,
Kuala Lumpur, Malaysia, 3 Discipline of Occupational Therapy, Faculty of Health Sciences, University of Sydney, Sydney, Australia, 4 Concord Cancer Centre, Concord
Repatriation and General Hospital, Concord, Sydney, Australia, 5 Sydney Medical School, The University of Sydney, Sydney, Australia
Abstract
Background: Cognitive impairment, colloquially termed ‘‘chemobrain’’, occurs in 10–40% of all cancer patients, and is an
emerging target of cancer survivorship research.
Aim: This study reviews published qualitative studies to explore cognitive impairments or chemobrain among breast cancer
survivors, with particular attention given to the impact on quality of life.
Method: Using keywords, we searched ten electronic databases (CINAHL, EMBASE, Proquest, OVID SP, MEDLINE, Oxford
Journal, Science Direct, PubMED).
Findings: Of 457 papers, seven relevant papers were included. Data was extracted and concepts were analysed using a
meta ethnography approach. Four second order intepretations were identified, on the basis of which, four third order
intrepretations were constructed. Linked together in a line of argument, was a consistent account on their struggles to selfmanage the chemobrain impairments that impact their daily lives. Five concepts emerged from the analysis of the primary
findings: i) real experiences of cognitive changes, ii) calls for help, iii) impact of cognitive impairments, iv) coping and v)
survivorship and meaning. Further synthesis resulted in four new order intepretations: i) The chemobrain struggle, ii) The
substantial impact of chemobrain on life domains, iii) The struggle to readjust and to self manage, and iv) ‘thankful yet
fearful’ representation.
Discussion: Awareness of cognitive changes were context-dependent on healthcare settings and cultural contexts as strong
determinants. Subjects verified the existence of chemobrain but healthcare providers mis-recognised, under-recognised,
and sometimes negated it perhaps due to its unknown aetiology. Asian breast cancer survivors appear less vocal than their
western counterparts.
Conclusion: The current literature on the lived experiences of how women experienced chemobrain provides a consistent
report that chemobrain is real, persistent and with detrimental impacts on quality of life - manifested as a constant
struggles. A greater awareness of the effects of chemobrain with improved functional assessment and interventions is
warranted.
Citation: Selamat MH, Loh SY, Mackenzie L, Vardy J (2014) Chemobrain Experienced by Breast Cancer Survivors: A Meta-Ethnography Study Investigating
Research and Care Implications. PLoS ONE 9(9): e108002. doi:10.1371/journal.pone.0108002
Editor: Gayle E. Woloschak, Northwestern University Feinberg School of Medicine, United States of America
Received January 21, 2014; Accepted August 24, 2014; Published September 26, 2014
Copyright: ß 2014 Selamat et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: The authors confirm that all data underlying the findings are fully available without restriction. Data are from the qualitative chemobrain
study whose authors may be contacted at syloh@um.edu.my.
Funding: This study is funded by the University Malaya Research Grant (UMRG 477/12htm). The funders had no role in study design, data collection and analysis,
decision to publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
* Email: syloh@um.edu.my
from 63% in the early 1960s to 90% in 2011 [3]. With the rise in
survivors, attention is turning to studying the longer-term adverse
effects of treatment and the impact they can have on daily
activities of living, participation and functioning by occupational
therapists. The phenomena of cognitive impairment after cancer,
is gaining increasing attention as one of the key foci of cancer
survivorship research by health professionals.
Introduction
Cancer survivorship is an emerging field of study and
development. Today, there is a steep rise in numbers of cancer
survivors internationally, due to earlier detection, better chemotherapeutic regimens and multidisciplinary collaborative care
approaches [1,2]. In the United State alone, the 5-year relative
survival rate for female breast cancer has improved significantly
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Chemobrain in Breast Cancer Survivors
Cognitive impairment is being acknowledged as an after-effect
of cancer treatment, and is also commonly known as ‘chemofog’ or
‘chemobrain’ [4–9]. Matsuda et al. [7] reported that chemotherapy-induced cognitive deficits occurred in 10–40% of all cancer
patients, with up to 23% in women with breast cancer [6]. Overall,
the estimated prevalance of chemobrain varies in the literature
from 15% to 70% [10]. The aetiology of chemobrain remains
unknown. However, there are indications that it may be due to
toxicity from chemotherapy agents, especially high dose treatments [11]. Hypotheses of the mechanisms involved include
vascular injuries and oxidative damage, inflammation, direct
injuries to neurons, autoimmune responses, chemotherapy-induced anaemia and the presence of the apolipoprotein Ee4 (APOE
e4) allele [12]. Studies also suggest cognitive changes may be due
to a combination of psychological and medical factors associated
with adjuvant systemic therapy (e.g. low oestrogen and progesterone from chemotherapy) as well as anticancer hormonal
treatments (e.g. tamoxifen or aromatase inhibitors) [10,13,14].
Cognitive impairments have also been shown to occur prior to
chemotherapy, making it difficult to determine what is actually
due to the chemotherapy [6,14,15]. Cognitive performance can
also be influenced by common problems faced by cancer survivors
that may include pain, insomnia, depression and fatigue [16].
Many survivors of breast cancer complain of increased
difficulties with multi-tasking and slower mental processing time,
which become more noticeable once they try to resume their
normal activities. This is especially evident when they return to
work and particularly for those in intellectually demanding
occupations [17]. In a study by Wagner et al. [18] 63% of cancer
survivors reported problems with concentration and attention,
50% problems with memory, and 38% problems with abstract
reasoning. The review by Matsuda et al. [7] identified cognitive
impairments related to memory loss and inattention [15]; and
problems with concentration, visuo-spatial skills, and motor
function [6]. This had detrimental consequences on work
performance (75%) that required patients to utilize compensatory
strategies (58%), with accompanying patient frustration (50%) as
well as adverse impacts on family relationships (33%) [18]. Overall
these studies highlighted that cancer survivors commonly reported
greater difficulties in work related activity with either a decrease in
functional ability or maintenance of functional ability levels that
required increased mental effort [19].
However, none of these studies captured the lived experiences
or the levels of severity of chemobrain symptoms experienced by
cancer survivors. It is therefore important for several reasons to
undertake an in-depth exploration of this issue, to understand the
cognitive changes experienced by breast cancer survivors. Firstly: i)
due to high survival rates, breast cancer patients are likely to live
with these problems for a considerable time – making it highly
pertinent to explore the impact of these cognitive impairments on
their quality of life. Secondly, there is no published meta-review of
qualitative studies addressing the chemobrain experience. A
qualitative review is a relevant approach to evaluate the meaning
that breast cancer survivors ascribe to cognitive changes, and it
represents an area of concern that would not be feasible to be
examined using quantitative approaches. Qualitative approach
variables are flexible and better able to explore specific relationships while taking into account the complexity of individual
contexts [20–22]. Therefore, the aim of this study was to review
qualitative studies that explored the lived experience of chemobrain among breast cancer survivors, with particular attention
given to the impact of chemobrain on daily living and quality of
life.
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Methods
This study is the first part of a larger study involving focus group
on survivors. The ethic to conduct the study was approved by
University Malaya Ethical Committee Boards. Using a metaethnography method, the interpretation of results from a range of
original studies were compared and translated to acquire a greater
understanding of the cognitive changes experienced by breast
cancer survivors [22–25]. We used the 7–step process of metaethnography by Noblit and Hare [25] -: 1. Developing a specific
research question; 2. Deciding what is relevant to the research
question; 3. Reviewing each study to identify key concepts and
recording them; 4. Determining how the studies are related, and
comparing study approaches to the key concepts; 5. Translating
the studies into one another; 6. Synthesising the translation
outcomes, and 7. Expressing the synthesis.
Step 5 above involved the researchers interpreting and
translating the key concepts via:- i) reciprocal translation (i.e.
studies with similar findings were directly compared and
synthesised), ii) refutational translation (i.e. studies rebutting each
other with conflicts of findings), and iii) Lines of Argument (i.e.
translation of the studies to build a final interpretation using both
differences and similarities among studies) [23].
Based on these steps, the researchers (MHS &SYL) independently appraised the selected papers and undertook the steps to
extract the information and synthesize the findings. Further
discussions took place between the reviewers when any discrepancies arose. Next, second order intepretations were identified, on
the basis of which, third order intrepretations (based on key
concepts and second-order interpretations) were constructed.
These were all linked together in a line of argument [(i.e. the
final interpretation using both differences and similarities among
studies) to present the intrepretation of cognitive impairments
experienced by women. The synthesis can be expressed as text as
well as in summary tables, diagrams or models, which can produce
significant new insights into the topic [23]. Finally a table synthesis
of concepts and order interpretation was built to connect each of
the papers.
Search strategy
We undertook a systematic search of the literature for all
published English language articles from 2002–2013 that used
qualitative methods to investigate post-chemotherapy cognitive
impairments for women with breast cancer. The following
databases were searched: CINAHL, Web of Knowledge, EMBASE, Proquest, OVID SP, MEDLINE, Oxford Journal, Science
Direct, PubMED, and Wiley.
Researchers performed free text searches by using keywords of
chemobrain OR (chemotherapy AND mild cognitive impairment)
OR post-chemotherapy cognitive changes. Next, we add in, the
term ‘‘ breast cancer survivors’’ AND qualitative. The search
filters were used at this stage to address the inclusion criteria for
the study.
The inclusion criteria were: 1) breast cancer and chemobrain.
The terms used were chemofog, cognitive dysfunction, cognitive
changes. Chemobrain was referred to as any domain of cognition
decline or dysfunction experienced by survivors who had
chemotherapy; 2) qualitative study. Terms used included lived
experience and qualitative experience; 3) studies published from
2002 to 2014. All papers published within the last 10 years; 4)
English language text and; 5) full text publication. The exclusion
criteria included: 1) study design other than a qualitative design
methodology; 2) studies with patients with cancers other than
breast cancer; and 3) non English papers.
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Chemobrain in Breast Cancer Survivors
Figure 1. This is the Figure 1 Search strategy.
doi:10.1371/journal.pone.0108002.g001
studies are usually evaluated using agreed criteria about data
collection and analysis processes that need to be fulfilled in order
to contribute to a review of findings. The first two questions act as
the core criteria in selecting the qualitative reports [28].
Nevertheless, the process itself is useful as it may contribute to
the richness and the focus of discussion [23]. Appraisal of the
selected studies contributed to the synthesis of the findings of the
review, as any critique of the studies could be identified [29] and
incorporated into the review. Table 1 outlines the CASP criteria
used to evaluate quality. The first two questions are screening
questions. If the answer to both is ‘‘yes’’, it is worth proceeding
with the remaining questions.
The second step of the Noblit and Hare process [23] involved
deciding what studies were relevant to our research question and
aims. In particular, the research team were interested to
understand women’s lived experience of chemobrain. The process
of the search strategy is detailed in Figure 1.
Quality Appraisal
Quality appraisal instruments are available to apply to
qualitative research reviews in a consistent manner, to ensure
credibility or trustworthiness of the findings [26]. We adopted the
‘Critical Appraisal Skills Program’, or CASP [27] format to
appraise each article in order to apply a valid, reliable and
objective method prior to synthesis. The CASP checklist is a 10item tool to appraise qualitative papers without using a numerical
score. This is to remind researchers of the importance of every
criterion in a qualitative paper in order to reduce bias. Bias in
qualitative research is usually related to the influence of
researchers and a lack of transparency in data collection and
analysis, whereas in positivist quantitative studies, bias is related to
representativeness and generalizability. Therefore, qualitative
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Interpretation with an analytic lens
This study used a seven-step process of meta-ethnography as
outlined by Noblit and Hare [25]. Two of the authors (MHS &
SYL) independently reviewed the identified studies from the
search and appraised the selected papers and undertook the seven
steps [22] to extract information and synthesize the findings. Next,
discussions took place between the reviewers and other authors
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Table 1. Critical Appraisal Skill Program (CASP Quality appraisal criteria).
1. Was there a clear statement of the aims of the research?
2. Is a qualitative methodology appropriate?
3. Was the research design appropriate to address the aims of the research?
4. Was the recruitment strategy appropriate to the aims of the research?
5. Were the data collected in a way that addressed the research issue?
6. Has the relationship between researcher and survivors been adequately considered?
7. Have ethical issues been taken into consideration?
8. Was the data analysis sufficiently rigorous?
9. Is there a clear statement of findings?
10. How valuable is the research?
The first two questions are screening questions. If the answer to both is ‘‘yes’’, it is worth proceeding with the remaining questions. Record a ‘‘yes’’, ‘‘no’’ or ‘‘cannot tell’’
to most of the questions.
doi:10.1371/journal.pone.0108002.t001
where discrepancies arose from collecting and categorising data of
each selected study to form the primary dataset. Table 2 outlines
the idea of the first process, or gathering of all concepts across the
studies, based on subjects’ experiences, as reported by each of the
study authors and suggested by Schultz [30]. During this early
stage, interpretation was avoided to maintain the original
outcomes of each article.
During steps three to five (Noblit and Hare 1988) the research
team identified key concepts through reciprocal translation (similar
findings) and refutational translation (conflicting findings) and the
interpretation of findings were taken together. These processes of
explicitly relating the papers occurs on three levels [30]. We
systematically followed Schultz’s process to interpret and explain
the results via analysis of key methaphors, and were careful not to
reduce the qualitative accents but to retain the sense of the account
of the women as reported in the papers. Schultz’s concepts of firstorder refer to the daily perceptions of the common people; the
second-order construct refers to the constructs of findings from the
scientific view in the papers, and the third order constructs are
final synthesis derived from the key concepts and second order
contructs based on the interpetations of the review authors [24].
contributed the theoretical perspectives for the review, SYL is
experienced in self management of women following breast
cancer, JV contributed medical and clinical encounters with
women being treated for breast cancer and LM brought the
perspective of an expert-patient with personal experience of breast
cancer.
Results
Qualitative studies identified for review
A total of 3628 papers were identified electronically following
the search using the keywords ‘‘chemobrain’’ and ‘‘chemotherapy’’ and ‘‘mild cognitive impairment’’. These papers were further
scanned for their relevance and this process reduced the number
to 457 articles. Next, the criteria for inclusion were applied to the
abstracts and this resulted in 83 articles. Further examination of
the full versions of these papers, according to the boundaries set by
the focused research aim for this study resulted in seven papers
that met the inclusion criteria for the review. Some of the
qualitative papers did not include the study design in the titles of
the publications, so it was necessary for the researchers to read and
screen the methodology sections to ensure that a qualitative design
was used. The full text for each of these seven papers was obtained
and each study was appraised. Figure 1 outlines the search results
for the review.
Theoretical framework for the review: The Illness
Representation Theory
To guide the synthesis for this review, the Model of Illness
Representation by Laventhal et al. [31] was adopted. This allowed
researchers to capture individual perceptions of illness related to
cognitive impairments experienced. This model consists of seven
components of illness representation: 1) Identity, or the name or
label of a threat; 2) Timeline, or the belief about the time trajectory
for the illness; 3) Consequences, or the perceived consequence of a
threat from the illness; 4) Cause, or the perceived causal
mechanism of any threats; 5) Control/Cure, or whether something
can be done to control the threat; 6) Illness Coherence, or whether
a person thinks about the threat in a coherent way, and 7)
Emotional representation, or the emotions associated with the
illness experience. This framework is particularly relevant to the
review topic and enabled the researchers to interpret and capture
the reasoning and self management issues for women experiencing
chemobrain.
Results of the quality appraisal process
Based on the CASP checklist (Table 1) as outlined in the
methodology section, five of the seven papers were considered to
have met all the quality criteria as judged by the reviewers.
Table 2 below showed the result of the critical appraisal skill
program (CASP)’s quality appraisal for the seven selected papers.
The researchers record a ‘‘yes’’, ‘‘no’’ or ‘‘cannot tell’’ to each
questions and then discuss to reach a consensus. Two studies did
not meet one quality criterion, which concerned the adequacy of
consideration of the relationship between researchers and survivors. These two studies were still included in the review since the
unmet criterion was judged to be a minor issue and did not
adversely affect the relevance of the studies to the objectives of this
review.
Researcher positionality
Results of the qualitative review of data extracted
Inevitably the interpretations of the study data from the review
will be influenced in some way by the interests and experiences of
the researchers, as researchers were the instruments of both the
data collection and the data analysis for the review. Therefore, it
was important that the researchers reflected on their own biases in
order to overcome them in the data analysis process. MH
Table 3 outlines the summary of each of the selected papers for
review and identifies the themes from each individual study. Based
on the synthesis-of-order [25,26,29,30] process, this table summarises the first order constructs that reflect the understandings of the
participants from each study and are usually summarised in the
results section of each article. Four themes emerged from the
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Y
Index N = No, Y = Yes, C = Cannot tell.
doi:10.1371/journal.pone.0108002.t002
Y
Y
Y
Y
Y
Y
Y
N
N
Y
Y
Y
Y
analysis of the seven selected papers-: i) The chemobrain struggles,
ii) The substantial impact from chemobrain, iii) The struggle to
adjust and self manage and iv) The ‘thankful yet fearful’ attitudinal
representation. Four second order intepretations were identified,
on the basis of which four third order intrepretations (based on key
concepts and second-order interpretations) were constructed.
These were all linked together in a line of argument that accounts
for survivors struggles to self-manage the chemobrain impairment
that impacted their activities of daily living.
Table 4 outlines the meta-ethnography process that utilises the
Schultz [30] notions of first, second, and third order constructs as
the follow-up analysis.
i) The chemobrain struggle. Chemobrain or chemotherapy-associated cognitive impairment was reported consistently as a
real experience. The signs and symptoms were noticed by women
with breast cancer, who described them in various ways. The term
chemobrain offers a quick reference to a concept that may easily
encapsulate a range of experiences and enable women to attribute
their experiences to a concrete term. However, chemobrain was
experienced as a struggle as the manifestation of the signs and
symptoms triggered the survivors to continually question its
existence, and to question if their experience was ‘real or not’.
There was a need to seek confirmation via various means, yet the
situation remained unresolved as there was no clear answer to
their question, leading to a persistent struggle within themselves
and with significant others.
Most women felt that chemobrain was an outcome of cancer
and its treatment, and perceived themselves to be ‘‘chemobrain
victims’’ [32]. Studies used indirect probes to gain descriptions of
the experience of chemobrain. and these validated the cognitive
changes by providing descriptions such as not being ‘as-sharp or
quick’ as before, or feeling ‘foggy’ or ‘spacey’ after treatment [33].
In a study involving Asian women, participants were only able to
identify the term chemobrain or describe the symptoms when they
were being indirectly probed about their experiences [34].
Survivors noticed cognitive changes during and after chemotherapy treatment [35]. Most of the breast cancer survivors reported
changes in the cognitive domains of short and long term memory,
processing speed, attention, concentration, language, verbal
memory and executive functioning [32,33,35,36].
Although other confounding factors (e.g. cancer related fatigue,
mood changes, lack of mental and physical activity, the cancer
condition, ageing, hormonal therapy, lack of social support and
menopausal status [33,34], have been found to induce or worsen
sustained cognitive issues, many survivors disagreed with this.
They justified that they had problems with attention and
concentration, although they agreed that they may be more easily
distracted when they were tired [33,34]. Multi-tasking in
particular seemed to cause concern and often resulted in feelings
of anxiety and frustration [32,35]. Survivors often described
chemobrain as ‘‘frustrating’’, ‘‘upsetting’’ and some were frightened by problems in processing new information. This phenomenon was perceived to affect their emotions as they struggled to
understand the changes occurring.
Y
Y
Y
Y
Thielen 2008 [38]
Boykoff et al. 2009 [37]
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
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Myers 2012 [36]
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Munir et al. [35]
Cheung et al. 2012 [34]
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
N
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Von Ah et al. 2013 [33]
Mulrooney Tamsin 2007 [32]
[2]
[1]
CASP Criteria from Table 1
Table 2. Critical Appraisal Skill Program (CASP)’s Quality appraisal for selected papers.
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
Chemobrain in Breast Cancer Survivors
Timing of onset of Chemobrain
The onset of chemobrain has been reported at different times
across the illness trajectory. Survivors had difficulty giving an exact
time of onset of the chemobrain symptoms; however they seemed
to lessen over time but not fully resolve [32,36]. Some survivors
reported they experienced changes in cognitive functioning after
diagnosis, during chemotherapy or after one to two months of
treatment [33,34,36], with most reporting that they continued to
experience it after the completion of chemotherapy [33,34]. A
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Chemobrain in Breast Cancer Survivors
Table 3. Characteristics of the selected studies.
Aim
Sample & method
Findings
Conclusion
Limitation
Von Ah
et al. (2013)
USA. [31]
To obtain a better
understanding of breast
cancer survivors’
experiences of perceived
cognitive impairment, its
trajectory,
and its impact on
relationship, daily
functioning, work and
overall life satisfaction
after breast cancer
diagnosis and treatment.
n = 22 breast cancer
survivors who reported
cognitive impairment
at least 1 year
postchemotherapy
treatment. Interview
and content analysis
approach.
Expressed concern in 6 major
domains of cognition: short term
memory, long term memory,
speed of processing, attention
and concentration, language and
executive functioning.
Chemobrain is frustrating,
affects self-confidence and social
relationships. Difficulties in work
and adapt using compensatory
strategies. Validation of perceived
cognitive impairment is important
for adjustment.
Perceived cognitive deficits
have broad implications for
wellbeing. Study provides
direction for theory
development, measurement
selection and additional
targets. Greater understanding
leads to development of
effective treatment of these
symptoms.
Limited by sample
characteristics
(geographic area and
homogenous). Self
report might be
influenced by previous
participation in cognitive
behavioral trial.
Myers,
(2012)
USA. [34]
To provide an in depth
description of the
experience of
chemotherapy-related
cognitive impairment for
women with breast cancer
and identify related
information that women
would find useful prior to
chemotherapy and
cognitive changes
n = 18 breast cancer
survivors who reported
cognitive changes
within 6–12months
postchemotherapy.
Focus group
discussion, semi
structured interview
and content analysis
approach.
Survivors describe difficulty of
cogntive changes and the
impact in daily living. Survivors
shares their coping skills
strategies. Survivors want to
get information prior to intiating
chemotherapy and psychosocial
education.
It provides a framework for
better understanding
regarding the changes that
can be used as a guide for
patient and family education
and generates questions for
additional research.
Coding was performed
by single investigator
and as such may be
biased. Interpretation by
only one individual
poses bias.
Cheung
et al. (2012)
Singapore.
[32]
To gather descriptions
from multiethnic breast
cancer survivors on their
experiences and impact of
chemotherapy- associated
cognitive changes on daily
lives and the coping
strategies.
n = 43 breast cancer
patient receiving
chemotherapy- Focus
group discussion
and thematic analysis.
Survivors were unfamiliar with
the term’chemobrain’ and
viewed it as a result of physical
and psychosocial adverse effects.
Encoutered memory loss, difficulty
in decision making, speech
problems. Married women
claimed frustrations that limited
their role as homemaker. Selfidentification of coping strategies.
This phenomenon is unfamiliar
to most Asians yet it impacted
their daily lives. Results
suggested that a culturally
relevant approach should be
adopted to evaluate and
manage cognitive changes in
these patients.
Selection bias due to
nonrandomized sample
recruitment and
response rate was low.
No baseline assessment
was conducted.
Heterogenous group.
Priming effects and
preexisting knowledge
of chemobrain.
Munir
et al.
(2009)
UK. [33]
To investigate
women’s awareness of
chemotherapy-induced
cognitive changes, their
perception of cognitive
limitations in carrying out
daily tasks and subsequent
return to work decision
and perception of work
ability.
n = 13 breast cancer
survivors who
completed
chemotherapy
between 12 months
to 10 years ago who
have returned to work.
Semi structured
interview with two
focus groups. Using
template analysis.
Survivors noticed decline lasting
about a year or longer in
concentration, confusion and
lack of clear thinking. Chemobrain
negatively affects self confidence
in cognitive ability and return to
work, but support from collegues
and employers increased
confident in cognitive skills.
Impact related to work ability:
poor memory, concentration,
difficulties in thinking quickly,
organising information and
decision making. Insufficient
information regarding cognitive
side effects from oncology
team or support groups.
Chemotherapy-induced
This study does not
cognitive impairment affected explore issues in
returning to work and
sufficient depth.
subsequent work ability. Return
to work and ability to manage
work were influenced by three
interrelated factors: 1) actual
cognitive ability following
chemotherapy, (2) awareness
of cognitive failures by the
women and their families, & 3)
subsequent impact on their
confidence in carrying out daily
tasks including work tasks.
Boykoff
et al. (2009)
USA. [35]
To document in-depth
the effects that cognitive
impairment has on
women’s personal and
professional lives.
n = 74 white and
African American
breast cancer
survivors who
experienced side
effects at least 1 year
beyond completion.
Focus group/in-depth
interviews and content
analysis approach
Cognitive impairment can be
problematic for survivors.
Survivors reported it diminished
quality of life and daily
functioning. Survivors
suggested a range of coping
strategies to manage social
and profesional lives.
Chemobrain impacts survivors’
economically, emotionally and
interpersonally. More research
needed on psychosocials
aspect of post treatment
symptoms to inform the efforts
of medical and mental health
communities.
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6
This study was non
randomised and
participants self
nominated for the study.
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Chemobrain in Breast Cancer Survivors
Table 3. Cont.
Aim
Sample & method
Findings
Conclusion
Limitation
Thielen
(2008)
USA. [36]
To explore the lived
experiences of the
neurological changes
women describe while
undergoing chemotherapy
for breast cancer
n = 13 breast cancer
patients undergoing
or completed adjuvant
chemotherapy within
12 months.
Interviews. A
Descriptive
phenomenological
method guided
analysis
Validated the existence of
chemobrain phenomenon
Women described it affects
daily living. These findings
may be useful for designing
questionaires, educational
products and interventional
strategies.
A decrease in cognitive
function is multifactorial in
origin. The womens’ feelings,
meaning and perceptions
contribute to the fundamental
of the lived phenomenon.
Small sample size:
Participants were not of
mixed ethnicity: sample
were from caucasian
women. Inexperienced
researcher.
Mulrooney
Tamsin (2007)
USA. [30]
To describe lived
experiences of self reported
cognitive impairment in a
sample of women who were
treated with chemotherapy
for breast cancer.
n = 10 women with
breast cancer – treated
with chemotherapy
within last 15–52
months. Interviews. A
descriptive and
interpretative
Gadamerian
phenomenological
theory
Survivors described problems with The experiences of chemobrain
memory, learning, concentration, can impact all aspects of life
language and multitasking.
including work. Despite the
Incidents of chemobrain could
belief of chemotherapy as a
occur at anytime and affected the cause, other factors should be
ability to perform usual activities acknowledged.
at home and work. Relationship
changed among friends and family
Chemobrain caused by necessary
treatment of breast cancer. Survival
was paramount.
Small numbers,
homogenous
participants with similar
demographic
background, educational
levels.
1st order construct - Constructs that reflect participants’ understandings, as reported in the included studies and usually found in the results section of an article.
doi:10.1371/journal.pone.0108002.t003
community. Healthcare providers were also seen as a potential
source of support since they work closely with survivors. It has
been reported that many healthcare providers are more nonchalant about the phenomena of chemobrain. Survivors reported that
their healthcare providers did not discuss any issues relating to
chemobrain [33,36,37] and some were insensitive when survivors
made complaints about their experiences of cognitive deficits. It
seemed that the survivors were dissatisfied as they wanted
professional validation of their experience of chemobrain symptoms but they were largely ignored.
Healthcare providers often assumed that reported cognitive
changes were due to other variables such as, stress or the natural
ageing process, and were quick to label chemobrain as a misnomer
rationale offered was that during chemotherapy, many other acute
physical symptoms (such as nausea, vomiting, fatigue) could not be
ignored, and so survivors did not focus on the subtler cognitive
symptoms. Women tend to be overwhelmed by having to suddenly
adjust to the reality of a cancer diagnosis, starting chemotherapy
and having a potentially life-threatening illness, so that they
initially disregarded changes in memory or attention [33,37]. The
present information suggests that cognitive changes can remain a
long-term problem for breast cancer survivors.
Dealing with the symptoms or side effects of cancer treatment is
a challenge that requires support from others. Family and friends
were regarded as good social support systems who encouraged
survivors to engage in activities and return to their role in the
Table 4. Synthesis of concepts, with second and third order interpretations.
Third order
interpretations
Concepts
Second order interpretations
Experiences of cognitive changes: Trajectory of cognitive changes,
types of cognitive changes, cognitive domains affected, experiences of cognitive
changes, awareness of cognitive changes. Call for help and support: Healthcare
providers to inform of possible cognitive changes, respond to medical community,
how to teach me, Looking for answers in all the wrong places, underwhelming
information for an overwhelming experience
(a) Patients want validation that it is real and to
be prepared for cognitive changes; want health
staff to be proactive in addressing the issue;
a strategy viewed as able to reduce tension
and frustration of family members also
(b) The chemobrain
struggle
Impact of chemobrain: Self and social relationship – how I changed, daily
functioning, working life, psychosocial, financial, overall life satisfaction,
change in all aspects of functioning
(c) Significant impact of chemobrain phenomena
on self, family, social circle, daily living and work
performances.
(d) The substantial
impact of
chemobrain across
life domains
Coping: Trying my best to fit in, coping strategies, adjusting to fit in,
prior needs of information on cognitive side effects
(e) Ways of coping derived by survivors with
multiple strategies to help themselves to
overcome the phenomena.
(f) Struggling to self
manage (without
support from health
professionals)
Reflect on survivorship: Thankfulness - I am still alive, Apprehension - what
the future holds.
(g) Reflection on survivorship to attain normality and
regain function
(h) Thankful for life,
yet fearful of the
future
2nd order construct interpretations of participants’ understandings made by authors of these studies (and usually found in the discussion and conclusion section of an
article). 3rd order construct the synthesis of both first and second order constructs into a new model or theory about a phenomenon.
doi:10.1371/journal.pone.0108002.t004
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Chemobrain in Breast Cancer Survivors
in memory strategies to remember things more easily. In the Asian
study by Cheung et al. [34] the use of complementary or
alternative medicine was more popular than pharmacological
intervention as participants perceived these remedies would
enhance energy and improve blood circulation to the brain.
Coping strategies for some survivors meant avoiding situations that
required them to remember names and engage in social
conversation. Many survivors decided not to focus on their
disabilities and adapted their enviroment to cope with chemobrain
by telling people about their cognitive changes [37]. Other
survivors relied on their family members and co-workers to remind
them about important things [36,37].
iv) Thankful for life, yet fearful of the future. In spite of
the challenges of daily living activities, the psychosocial impact,
and the lack of support from many health providers during the
chemobrain experience, these factors did not cause women with
breast cancer to withdraw from chemotherapy treatment. Survivors appreciated receiving chemotherapy as it reduced their risk of
mortality. Most were grateful that they had survived and some
took their diagnosis as a turning point in their life. They worked
towards personal goals for self-satisfaction and some women
placed a higher priority on developing relationships with family
and friends and contributing to wider society [33,34].
[37,38]. Conversely, some women reported that they did receive
general information about the possibility of cognitive side-effects
from chemotherapy from the oncologists or oncology nurses [38],
although conversations were usually initiated by the survivors as
they sought explanations [32]. Women felt that early warnings and
validation of these changes from healthcare providers with patientinformation could help them cope proactively with these changes
[33,36,38]. Support groups may help survivors to identify or
recognise cognitive changes and to be better prepared [36].
ii) A substantial impact of chemobrain across life
domains. Women described the impact of chemobrain on
themselves, their social relationships, working life and daily living
[33]. Survivors reported that family and friends ranged from being
supportive to being unconcerned about their chemobrain experiences. Some women reported that the cognitive changes had
affected their psychological well-being and they lost selfconfidence
and self-esteem in the company of family members and friends.
Survivors were often confused by their cognitive changes and then
felt misunderstood or embarrassed. Survivors who were homemakers described memory difficulties adversely affecting their roles
in the family, and that some family members had a lack of
awareness about these changes. Some suggested their difficulties
maintaining their homemaker roles were related to their own
expectations about what they should be able to achieve
[33,34,37,38]. Some families provided considerable support as
they understood the issues and were aware of the cognitive
changes and this was related to positive cultural values. For
instance, Cheung et al. [34] reported that the Asian value for
living in communities and having a kindred spirit meant that
members of the community became a source of support.
Cognitive changes often impacted on working life and school
related activities. Survivors indicated that cognitive impairment
affected their confidence in returning to work because returning to
work would highlight their problems further and be too
challenging [35]. Survivors who had returned to work reported
that they were struggling to perform and complete tasks. Their job
performance had decreased due to an inability to maintain
attention or focus at work, to maintain their thoughts during
conversations and inability to comprehend a text without reading
it more than once. As a result, work tasks required more time and
they were less productive. For some, this difficulty contributed to
loss of employment and difficulties finding work [33,36,37].
Professional women in jobs that required a high level of cognitive
functioning were more negatively affected by chemobrain [32].
They reported that they needed more effort to perform tasks than
previously, and that as their jobs required several skill sets that
incorporated multiple cognitive domains, this created additional
challenges. Survivors found they required more attention to
complete work tasks to a sufficient standard [32,33,38]. Munir
et al. [35] found that survivors sometimes hid cognitive difficulties
from their employer. However the findings suggest that good
support from employers and colleagues, helped survivors to regain
confidence in returning to work.
iii) Struggling to adjust and to self manage. While
struggling to overcome cognitive changes, often without real
support or acknowledgement from health professionals, most
survivors developed their own strategies to overcome the effects of
chemobrain, to prevent further complications and to help them
cope with daily living and work functioning These are listed in
Table 5. Two studies out of the seven reviewed [33,35] did not
discuss any coping strategies.
The majority of the survivors used non pharmacological
strategies such as mental activities, psychosocial management
and practical reminders, while some survivors trained themselves
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‘‘Life isn’t guaranteed, and I try not to be real pessimistic, but
it is sort of a wakeup call. You are not guaranteed that
tomorrow will come’’ [32], p. 122.
However, Thielen [38] reported that survivors were still living
in doubt about their cancer prognosis and the likely duration of
their chemobrain symptoms. They were apprehensive about the
situation as they had received little information about chemobrain.
This created additional stress for survivors who were attempting to
self-manage what they saw as obvious impairments, which were
not acknowledged by their health providers. This also led them to
adopt the belief that they should be grateful (to be alive), and
‘downplay’ cognitive impairment as a lesser issue to self manage
their return to their normal state.
Application of the experience of chemobrain to the
Leventhal [31] framework
The line-of argument synthesis [24] using the Laventhal model
enabled us to frame the significance of the burden of cognitive
impairment in cancer survivors. In Table 6 we attempted to
present each dimension of Illness Representation Theory [31] in
the context of the experiences of chemobrain from the reviewed
studies. The cognitive and emotional processes experienced by
women were captured and may influence their mental image of
potential threats attributable to chemobrain. The interpretation
that chemobrain is a relatively small issue (in comparison with
death for example), may underestimate the threat of the
debilitating effect chemobrain can have on everyday functioning
and quality of life. The burden of cognitive impairment in cancer
survivors appeared grossly underestimated. This warrants it to be
addressed promptly as studies have shown that illness perceptions
have associations with a number of negative outcomes in the
experience of chronic illness including self-management behaviours and quality of life [39], and this can be anticipated within the
breast cancer population.
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Chemobrain in Breast Cancer Survivors
Table 5. Coping strategies adopted by survivors.
COPING STRATEGIES
32
34
36
37
38
X
x
Pharmacological
Nutritional products
X
Complementary and alternative medicine
X
Non Pharmacological
Healthy lifestyle practices
X
X
Physical activities
X
X
x
x
X
Written
X
X
X
Use of technology
x
x
Mental activities
Practical reminders
doi:10.1371/journal.pone.0108002.t005
and emotional representations [31]. The idea of illness perceptions
is derived from self-regulation theory [31,40]. This theory
proposes that individuals form common-sense beliefs about their
symptoms to cope with any potential health threats. Our review
suggests that the breast cancer survivors were actively trying to
find some meaning to their chemobrain symptoms which became
more confronting when they resumed their daily activities.
Illness Representation Theory dictates that illness representations are mediated by influencing factors that have not been
adequately explained by the biomedical model of illness. A strong
thread of ‘struggling’ with the ‘why’, ‘how’ and ‘when’ of
chemobrain is manisfested cognitively and in survivors’ self
management behaviour. There is thus, a real gap in survivorship
care, as chemobrain becomes a consistently reported phenomena
associated with the rise in breast cancer survival rates. Coupled
with the unusual terminology of ‘chemobrain’, survivors have
Discussion
Implications of the experience of chemobrain
The meta-ethnography method facilitated the synthesis of seven
qualitative research studies, and the creation of a preliminary
notion to highlight the perceptions women with breast cancer have
about their experience of chemobrain. The application of the
Illness Representation Theory to the findings allowed further
interpretation of the meanings attributed to the chemobrain
experience. Although our analytical approach was inductive in
nature, it was helpful to consider a theoretical framework that
addressed meaning such as the construct of illness representation.
The Illness Representation Theory informed the analysis about
the ‘vague but real’ cognitive symptoms experienced by breast
cancer survivors, portrayed as broader health problems involving
identity, timeline, consequences, cause, control, illness coherence,
Table 6. Interpretation based on Illness Representation Theory – the struggle of Chemobrain.
Dimension
Potential Manifestations (per illness representation theory)
1. Identity
Matching or nonmatching of cognitive symptoms to the chemobrain experience (e.g., matching symptoms like feeling
foggy, not as sharp, not as quick refering to the chemobrain syndrome; or rationalizing it as ‘deficits are unimportant
compared to getting through treatment, surviving from cancer)
2. Timeline
Beliefs about the expected onset/duration of it (e.g., acute vs chronic or cyclical). Increasing reports of survivors belief that
chemobrain starts after they resume work, but most are unsure of exact timing. Some belief it is transient but others fear
its persistent impact. There will be some degree of struggle- transient to persistent
3. Consequences
The perceived and anticipated impact of chemobrain (e.g., reversible vs static vs progressive or permanent). Subjects
highlighted that chemobrain affected their daily functioning, economic status, and their social relationships. Some
believed these impacts may get better whilst others feared that the cognitive deficits may be permanent loses. The
underlying finding is that they will have to struggle with it.
4. Causes
They perceived the contextual factors or antecedent causes (e.g., aging, stress of having cancer and treatment, rather than
from treatment since there is no evidence on the mechanism and since their health providers did not validate chemobrain)
leading to a constant struggle.
5. Controllability
An expectation that chemobrain symptoms can be somewhat controlled via coping strategies, but may not be cured and
may even be permanent damage. Survivors were struggling to adjust. A belief that they should just self-manage since ‘‘it
does not seems to be a significant according to the health providers’.
6. Illness coherence
The subjects’ perceived understanding of the chemobrain phenomena – (ie vague, subtle, foggy, spacey) but the health
team did not validate it, suggesting a period of uncertain struggle.
7. Emotional representa-tions
Panic and frustrated in response to chemobrain experience
Sense of dissatisfaction and anger that they were not forewarned
Neutral or matter-of-fact emotional state (for some)
Again mansifesting a constant struggle within themselves and with significant others
Based on the Leventhal’s Common Sense Model of Illness Representation [31,40].
doi:10.1371/journal.pone.0108002.t006
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Chemobrain in Breast Cancer Survivors
Asian and western perspectives of women with breast
cancer. Based on the qualitative papers available in the review,
expressed that their health providers are negating its presence, and
are therefore not validating its existence. Common sense reasoning
is then left to fill the gap, so that cognitive issues are attributed to
stress or aging or other potential contextual factors. This leads the
survivors to arrive at a state of problem-solving where they struggle
to self manage an ‘unknown’ but real issue. The idea that women
should just manage as well as they can suggests a constant struggle
to cope. The final dimension of illness representation is a cognitive
representation of the issue, and this amounts to chemobrain being
considered insignificant compared to surviving cancer, despite
dissatisfaction with the situation and having to live with the
consequences.
the researchers found emerging differences in approach to their
chemobrain experience between the Asian and western subjects.
Our review suggested that Asian women are less familiar with the
chemobrain phenomena than their western counterparts, however
this needs to be interpreted with caution as it was based on only
one paper with a small sample size [34]. Asian cultures were
emotionally less expressive in emotion [50]. It has been suggested
that Asian women are more focused on completing their treatment
rather than being concerned with survivorship issues [34,40].
Nevertheless, the uniqueness of the perceptions of Asian women
should be taken into account in any discussion on the issue of
chemobrain. These women clearly verified that chemobrain was
not a myth, but a real daily experience for them, which became
apparent when they resumed daily duties. Many expressed that
they were thankful to be alive, and had adopted the belief that
chemobrain was just one of the changes that they need to adapt to
since survival was the ultimate outcome in overcoming breast
cancer. This tolerance of chemobrain symptoms may be best
explained by the medicalization of cancer treatment, and this has
contributed to the lack of recognition of chemobrain from the
medical fraternity.
For both Asian and western cancer survivors, medicalization of
the cancer journey is focused on efforts to battle the disease and at
the same time is a reminder to survivors that there is a risk of
cancer recurrence.
Implications for health services across health settings
Chemobrain or mild cognitive impairment associated with
chemotherapy treatment is consistently reported by breast cancer
survivors. There is a growing body of research, but the incidence
and causes remain uncertain due to inconsistent methods of
objective assessment of cognitive changes and subjective reports
from survivors [41,42]. Although many studies suggest that
chemobrain is related to cancer treatment such as chemotherapy
[43,44], it is essential to recognise the other confounding factors
such as psychological factors and insomnia that could contribute to
cognitive changes [45]. In order to enhance the quality of life of
survivors, healthcare providers should be reliable sources of
information about cognitive changes. A proactive inter-disciplinary team approach comprising the oncology medical staff and
allied health professionals is essential to ensure a holistic
partnership to provide better care, and to address the participation
needs of cancer patients [46].
A consistent evaluation of potential causative factors by health
professionals can help to explore the main causes and mechanisms
of chemobrain and assist in developing interventions for survivors
[46], however few studies have been completed to guide this
development. It must be highlighted that some medical clinicians
are reluctant to provide information on chemobrain, because of
the belief that patients may reject chemotherapy if they believe
there is a causal relationship between chemobrain and chemotherapy. Whilst the debate continues, women with breast cancer
may face dilemmas about continuing treatment which may lead to
worse adverse effects [8] Nevertheless, there are no data to suggest
that fears about chemobrain are likely to lead to withdrawal from
chemotherapy. In fact, the majority of participants indicated they
were willing to undergo chemotherapy despite side effects
[33,34,36]. However most of the participants stressed the
importance of getting early information regarding potential
cognitive changes. This needs to be a component of the informed
consent process prior to treatment. Our review suggests that most
survivors acknowledged their fears but were pragmatic and wanted
to be informed early.
‘… undermining efforts at self-determination and self-care;
and, keeping the patient’s life suspended by continual
reminders that death is just around the corner, and that all
the time and energy left must be devoted to ferreting out and
killing the disease’ [40], p.53.
The refusal or reluctance by some medical practitioners to
acknowledge the cognitive issues experienced by survivors may
lead to a lack of referrals to allied health professionals to address
issues like chemobrain. A lack of attention to chemobrain means
that the measurement of chemobrain symptoms is neglected. This
means that the extent of impairment cannot be defined, and may
decrease the impetus to develop effective interventions as
outcomes cannot be evaluated. This is a particular issue for the
management of return to work for survivors.
Self-management of chemobrain symptoms
Our review identified a lack of self-awareness about when
changes in cognitive functioning became obvious for survivors. It
seemed to be most apparent when they struggled to get work done,
engaged in their role as a home maker, socialised and tried to cope
with being less productive at work. Chemobrain led to specific
challenges in handling daily tasks. According to Vearncombe et al.
[46] the greatest decline was experienced in verbal learning and
memory for breast cancer survivors, with problems in concentration and memory functions, contributing to a decline in functional
performance. Inability to perform functional tasks that required
constant effort for survivors had resulted in emotional frustration,
mood changes and higher anxiety.
Apart from the personal difficulties experienced, our review
found that the impact of chemobrain extended to affecting
survivors’ social relationships. Survivors reported that they
withdrew from social situations to avoid feelings of embarrassment
about the effects of their chemobrain symptoms, and this caused
changes in their social relationships among family members,
Addressing cognitive impairments
Despite the need for information about chemobrain for
survivors, there are other needs to be considered. There is the
potential for some psychological consequences of perceiving a
threat from chemobrain which may be induced by the provision of
information about it [47]. Health care professionals do acknowledge cognitive changes as an issue for the survivors, although there
is a lack of scientific data regarding the aetiology [48] Health care
professionals, particularly oncologists, tend to emphasise the
management of physical side effects [49] or acute side effects
which have been reported by patients, as these are more
established in the literature.
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Chemobrain in Breast Cancer Survivors
friends and colleagues. If they had been prepared and had some
self-management guidance, these social consequences may have
been lessened or prevented.
In terms of self-managing chemobrain, cancer survivors
struggled and tried many ways to cope with impairments. Most
of the selected studies found that psychosocial interventions and
practical reminders were good sources of coping strategies. There
appeared to be some cultural differences in coping strategies for
chemobrain. Asian women were more likely to use complementary
and alternative medicine such as traditional Chinese medicine to
improve their cognitive function [34]. Further studies are needed
to explore how cultural beliefs and health setting models can
influence early health intervention and the coping strategies of
survivors. Research exploring how ethnicity or cultural background can affect how someone copes with chemobrain symptoms, and how they go about dealing with the situation, is a viable
and timely topic to minimise the gap in this field of cancer
survivorship studies.
States, one was from the United Kingdom and one was from the
Asian region. There is clearly a gap in studies from many other
geographical locations. Future studies should explore the differences between less developed countries and developed countries,
where the healthcare systems are uniquely different. Despite the
limitations, meta-ethnography is a useful method for synthesising
qualitative research conducted on a specific issue, and for
developing models that interpret findings across multiple studies
[28].
Conclusion
Our review found clear verification and consistent reports that
breast cancer survivors’ experiences of cognitive impairments were
real, with a reported disparity between health professional and
survivor’s viewpoints across different healthcare settings and
cultures. Persistent chemobrain clearly has a detrimental impact
on the economic, emotional and interpersonal status of breast
cancer survivors. Subjective self-report were validated by the
consistent findings across the studies, and it is likely that the
severity of difficulties experienced (manifested as ‘strugglings to self
manage’) was underestimated. Women may downplay the effect of
these impacts because of the lack of recognition from health
providers. The current literature on the lived experience of
chemobrain symptoms by women with breast cancer provides
(manifesting as a constant struggle on their daily living domains)
evidence that chemobrain is real, persistent and has substantial,
detrimental impacts on daily living and quality of life.
Reflectivity of conducting the metaethnography study
We did encounter some challenges in developing a new
synthesis of qualtitative research of a meta-ethnography study on
‘chemobrain, in particular in synthesizing methods from different
contexts and research traditions. Some issues we encountered were
the need to appraise the papers to ensure they fit our research
question, and the CASP quality.
Strengths and limitations of the study
The strength of this review is the direct insights obtained from
reports by breast cancer survivors about the cognitive changes they
experienced in real life. Synthesizing the data from various
qualitative researchers helped identify the scope and depth of the
key domains of cognitive impairments experienced across different
cohorts, time periods, cultures and health settings using a variety of
qualitative study methodologies. Using the meta-ethnography has
allowed a body of qualitative research studies to be combined
together in a systematic way, where we have attempted to
inductively analyse them through extracting concepts, metaphors
and themes arising from the seven different studies. Meta
ethnography has been proven useful where reflection on such
interpretative approaches are needed and it has been used widely
in health studies [22,23,51,52]. In short, the strength of this
approach lies in the way it was constructed to preserve the
meaning of the primary data and the help it gives us to look into a
theoretical underpinning to understand the chemobrain phenomenon in a new intepretation of synthesis [53,54]. However, whilst
the method followed a systematic process, it remained fundamentally inductive as it re-interpreted qualitative data presented across
several qualitative studies. Therefore, we conclude that these
findings can inform the development of recommendations for
health care professionals, including clinical practice guidelines on
patient education, assessment and interventions for breast cancer
survivors to address chemobrain symptoms.
Several limitations have been acknowledged in this review
study. We recognised the importance of maximum variation
sampling, however the number of studies included and the sample
size within each study was small. The inclusion criterion of
published sources with full text availability may have omitted the
inclusion of other potential sources such as unpublished theses or
published book chapters, and this may have reduced the richness
of the data. Five out of seven of the studies were from the United
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Recommendations
On the basis of the key findings discussed above, we recommend
the development of an information resource to create awareness of
potential cognitive changes associated with breast cancer treatment among patients, family caregivers and, perhaps most
importantly, among healthcare providers. A more objective testing
and monitoring of neurocognitive function in survivors complaining of cognitive changes is warranted. In addition, studies
evaluating cognitive testing should be derived from reliable,
functional and ecologically valid assessments which are culturally
defined, rather than depending only on pen and paper
assessments. Optimisation of some of the self-management
strategies used by the some breast cancer survivors can be used
to inform the development of educational information for
survivors, and for enhancing awareness among healthcare
providers. Further quantitative research is required to explore
the causal mechanisms associated with chemobrain symptoms.
Future research that includes systematic, longitudinal investigations of illness representation and its impact on health behaviours
among survivors with cognitive impairment is needed. Greater
awareness and culturally-specific therapy is critical to enhance
functional return to daily tasks and quality of life during the cancer
survivorship phase, especially related to return to work. Our study
findings contribute to both theoretical and empirical implications
for future research and the development of practice to address
cognition in cancer survivorship.
Author Contributions
Conceived and designed the experiments: SYL MHS. Performed the
experiments: MHS SYL. Analyzed the data: SYL MHS LM JV.
Contributed reagents/materials/analysis tools: SYL. Contributed to the
writing of the manuscript: MHS SYL LM JV.
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September 2014 | Volume 9 | Issue 9 | e108002