Psychology
2012. Vol.3, No.4, 304-309
Published Online April 2012 in SciRes (http://www.SciRP.org/journal/psych) http://dx.doi.org/10.4236/psych.2012.34043
Copyright © 2012 SciRes.
304
Quality of Life, Self-Efficacy and Psychological Well-Being in
Brazilian Adults with Cancer: A Longitudinal Study
Elisa Kern de Castro1, Clarissa Ponciano1, Bruna Meneghetti1,
Marina Kreling1, Carolina Chem2
1Sinos Valley University, São Leopoldo, Brazil
2Santa Rita Hospital, Porto Alegre, Brazil
Email: elisa.kerndecastro@gmail.com
Received October 25th, 2011; revised January 17th, 2012; accepted March 2nd, 2012
Quality of life (QoL) has been considered worthy of assessment in the treatment, prevention and rehabili-
tation of cancer patients. As it has a psychological dimension, is important to investigate the relationship
between quality of life and psychological concepts like self-efficacy and psychological well-being. Ob-
jective of the present study is to examine the QoL, self-efficacy and psychological well-being in adults
with cancer. Methods: 50 patients completed self-report questionnaires: WHOQOL-bref, General Self-
Efficacy Scale and GHQ-12 in two periods (T1 = timeline; T2 = follow up 1 year later). A paired t-test
did not identify significant differences in the QoL self-efficacy and psychological well-being between T1
and T2. However, men had a better overall QoL and in the physical and social dimensions, and psycho-
logical well-being in T1 compared with the women. In T2 there were significant differences between men
and women only in the social and psychological dimensions of the QoL. The self-efficacy in T2 was the
only predictive variable of the QoL in T2, explaining 71.9% of its variance. It is concluded that, in the pe-
riod of one year, the QoL, psychological well-being and self-efficacy were stable, but gender differences
were identified. The variables measured in T1 were incapable of predicting the QoL in T2. The gender
differences found in QoL and psychological well-being can be used to guide specific future interventions
with these patients.
Keywords: Cancer; Oncology; Quality of Life; Self-Efficacy; Well-Being; Longitudinal Study
Introduction
With advances in health areas the life expectancy of patients
with cancer has been prolonged, leading to concern regarding
the assistance for and quality of life (QoL) of these patients (Seidl
& Zannon, 2004). Thus, the concept of QoL has been used in
the area of health and has been considered worthy of assess-
ment in the treatment, prevention and rehabilitation of sick
patients.
The QoL is related to the health concept proposed by the
World Health Organization (WHO)—physical, mental and so-
cial well-being. It means the individual’s perception of his/her
own health generally speaking, according to his/her cultural
demands, value systems, goals, expectations and concerns. This
explains why individuals with similar objective indicators of
QoL can have quite different indices in the subjective QoL
(Seidl & Zannon, 2004; Mayo, Moriello, Asano, Van Der Spuy,
& Finck, 2010).
A recent systematic review of the Brazilian literature about
the QoL and cancer (Bertan & Castro, 2009) showed the grow-
ing number of empirical studies related to the issue, which, on
the whole, related the QoL to the impact of the disease and of
the treatment. Nevertheless, other issues were dealt with, as the
QoL and diagnosis and validation of instruments. In another
study Montazeri (2008), a bibliographic review was made about
the QoL in patients with breast cancer, encompassing all the
publications in English in biomedical publications, between
1974 and 2007. A large number of the articles dealt with the
construction and validation of instruments of assessment of the
QoL, surgical treatment, systemic therapy, the QoL as a pre-
dictor of survival, psychological suffering, care support, symp-
toms and sexual dysfunction disorders.
As it has a psychological dimension, the QoL has been re-
lated to different concepts of this nature, and one of them is
self-efficacy. According to Bandura (1997; 2001), self-efficacy
consists of beliefs and/or perceptions which individuals have
about their own potential to develop any type of activity pro-
vided that it generates the results desired. This belief in per-
sonal competence provides the basis for motivation of the hu-
man being, well-being, self-fulfillment and expectations of re-
sults (Bandura, 2001).
There is evidence of the importance of self-efficacy in pro-
ducing better results in health (Bandura, 1997). More specifi-
cally, concerning self-efficacy and the QoL of patients with
cancer, research has shown a positive association between these
two variables, including reduced stress of the patients (Kreitler,
Peleg, & Ehrenfeld, 2006), improved relations with caretakers,
and increased physical activities (Perkins, Baum, Taylor, &
Basen-Engquist, 2009).
As well as self-efficacy and the QoL, psychological well-
being is also a concept which has been associated with good
results in health. The meta-analytical study performed by How-
ell, Kern and Lyubomirsky, (2007) which assessed the impact
of more than 150 studies concerning well-being on health
showed that, both short- and long-term, well-being is related to
the capacity of controlling symptoms of diseases, especially
regarding the impact on the immunity system and resistance to
E. K. DE CASTRO ET AL.
pain. In patients with cancer, the concern has been to encourage
their psychological well-being and improve their QoL (Kwan,
Ergas, & Somkin, 2010; Ramachandra, Booth, Pieters, Vrotsou,
& Huppert, 2009). Rottman, Dalton, Christensen, Frederiksen
and Johansen (2010) found that, in women with breast cancer,
self-efficacy was a predictor of emotional well-being one year
afterwards, but was not related to physical and social well-
being.
Thus, the present study aimed to make a longitudinal as-
sessment (one year—T1: first data collection; T2: one year after
the first one) the quality of life, self-efficacy and psychological
well-being of adults with cancer, also examining possible dif-
ferences between men and women. Moreover, it sought to as-
sess the predictive power of these same variables in T1 and of
self-efficacy and well-being in T2 for the quality of life in T2.
From the studies reviewed, the hypothesis was that the three
constructs assessed would be strongly correlated in the two data
collection stages and that, one year after the first assessment,
the patients would have higher indices of the quality of life and
psychological well-being due to being more adapted to the
treatment. It was also expected that the quality of life of all the
variables measured in T1 would predict the quality of life in T2.
Material and Methods
Participants
50 youthful patients with different types of cancer, with an
average age of 33.3 years old (SD = 5.5) took part in the study
both in T1 and T21. All the participants were outpatients in the
Unique Health System (SUS) at a reference hospital in the
treatment of cancer in a town in the south of Brazil. The pa-
tients were selected in a consecutive manner among those
waiting for medical appointments at the outpatients unit of the
hospital in T1. For the present study, the sample only refers to
patients who responded to all the instruments in the two data
collections (T1 and T2). The main types of cancer diagnosed in
the patients of the sample were as follows: breast (16), rectum
(4), uterus (4), melanoma (3), sarcoma (3), and mouth (3),
among other less frequent types totaling 17 patients. The aver-
age of time since diagnosis was 2.8 years old. Fifteen (30%) of
the patients in T2 were in treatment to control metastasis,
whereas 35 patients (70%) were in maintenance treatment. In
Table 1 there is other biosociodemographic data of those par-
ticipating in the study.
Instruments
World Health Organization Quality of Life Assessment In-
strument—short version (WHOQOL-bref) (Fleck et al., 2000):
instrument developed by the WHO which aims to assess the
QoL in different cultures. The WHOQOL-bref consists of two
general questions and 24 questions which compose each one of
the 24 facets making up the original instrument of 100 ques-
tions. The four domains of the instrument are: physical, psy-
chological, social relations and environment. For each question
there are five degrees of intensity. The higher the individual’s
score in the questionnaire, the better his/her QoL is. Concerning
Table 1.
Biosociodemographic and clinical data.
T1/N (%) T2/N (%)
Sex Male 17 (34%) -
Female 33 (66%) -
Schooling Elementary incomplete 21 (42%) -
Elementary complete 6 (12%) -
High school incomplete 6 (12%) -
Secondary complete 11 (22%) -
Higher education
incomplete 6 (12%) -
Work Works 24 (48%) 19 (38%)
Does not work due
to the disease 20 (40%) 31 (62%)
Marital status Single/Separated 17 (34%) 18 (36%)
Married/Lives together 33 (66%) 31 (62%)
Widow(er) - 1 (2%)
Metastasis No 38 (76%) 35 (70%)
Yes 12 (24%) 15 (30%)
Family history
of cancer No 14 (28%) -
Yes 32 (72%) -
Type of
treatment used Chemotherapy 30 (60%) 18 (36%)
Radiotherapy 23 (46%) 8 (16%)
Surgery 44 (88%) 17 (34%)
Admission in the
last year No - 35 (70%)
Yes - 13 (30%)
the internal consistency, Cronbach’s Alpha value in the present
study was 0.71 (T1) and 0.86 (T2) for the total QoL.
General Health Questionnaire—GHQ-12 (Goldberg, 1978;
Gouveia et al., 2003): It is a series of 12 statements about the
state of health of people in general, and aims to identify psychi-
atric diseases which are not serious. The individual’s task con-
sists of saying if the statements apply to him/her, or not. The
GHQ-12 is a short version of the instrument, derived from the
original scale which consists of 60 items. The higher the score
on the instrument, the greater his/her symptoms of psychiatric
diseases and, therefore, the less his/her well-being. In the pre-
sent study, Cronbach’s Alpha was 0.85 (T1) and 0.89 (T2).
General Perceived Self-Efficacy Scale (Schwarzer, Boehmer,
Luszczynska, Mohamed, & Knoll, 2005): It consists of 10
items which assess the individual’s perception of self-efficacy,
and the answers vary from 1 (it is not true) to 4 (it is always
true). Higher scores indicate a greater perception of self-effi-
cacy. The Brazilian Portuguese version was used in studies
which did not aim to gather information about the psychometric
properties of the scale, but the scale had a very high reliability
(Teixeira, & Dias, 2005). Cronbach’s Alpha of the scale in the
present study was 0.82 (T1) and 0.83 (T2).
1In T1 151 patients took part, but in T2 it was perceived in the hospital
records that 16 patients had died, 15 patients refused to take part in the se-
cond phase and 80 patients were not located (they were not undergoing
hospital treatment, and the hospital records were not updated in order to
allow contact to be made again).
Design and Procedures
The study is of a longitudinal nature. Both the first data col-
Copyright © 2012 SciRes. 305
E. K. DE CASTRO ET AL.
Copyright © 2012 SciRes.
306
lection (T1) and the second one, twelve months after the first
one (T2), occurred in a hospital specialized in cancer. The re-
searchers in T1 found in the hospital records those patients who
were undergoing treatment for cancer. Having identified the
patients, they were invited to take part in the study and were
taken to a room in the outpatients unit of the hospital.
The instruments were filled in by the interviewers, who read
the questions aloud and marked the option matching the answer
of those taking part. It was decided not to use the self-applica-
tion form of the instruments as many patients had little school-
ing and difficulty in reading and filling in the questionnaire. In
T1, the questionnaires were applied before the routine medical
appointments of the patients, in a reserved room. In T2, the
instruments were applied in the same place, but the meeting
was scheduled beforehand by telephone.
Research Ethical Procedures
This study was previously approved by the Ethics Committee
of the Santa Rita Hospital. All the participants signed the In-
formed Consent before the questionnaires were applied.
Data analysis
All the research protocol data was tabulated in the database
of program SPSS 18.0. The confirmation of the parametric
criteria of the sample and the internal consistency of each in-
strument were analyzed. Then, the test of Pearson’s correlation
was applied in order to assess the correlations between the QoL,
self-efficacy and psychological well-being in T1 and T2. Af-
terwards, a paired t-test was performed to assess possible dif-
ferences between the measures of the QoL, self-efficacy and
general health between T1 and T2, and so was the independent
t-test in order to compare the level of the QoL, self-efficacy and
general health as per the gender of the participants. Finally,
linear regression analysis (stepwise method) was performed to
assess the predictive power of the independent variables which
had a significant correlation with the QoL in T1, well-being in
T1 and T2 and self-efficacy in T2 for the QoL in T2.
Results
Initially, the analysis of the test of Pearson’s correlation
showed that in T1 the total QoL and all its dimensions corre-
lated positively in a moderate to strong manner with the
self-efficacy in T1 and negatively with the well-being in T1,
indicating that the greater the self-efficacy and psychological
well-being, the greater the QoL (as per Table 2). Also in T1,
the self-efficacy and psychological well-being also had signify-
cant and moderately negative correlations, indicating that the
greater self-efficacy was related to higher indices of well-being.
The results of the total QoL and its dimensions in T1 and T2
were not significantly correlated. In T2, the self-efficacy corre-
lated significantly with the total QoL and its physical dimen-
sion, and the psychological well-being in T2 correlated signify-
cantly and negatively with the total QoL in T2 and with the
physical, social and environmental dimensions.
Next, the paired t-test was performed in order to compare the
averages of the total QoL and its dimensions, self-efficacy and
psychological well-being longitudinally (T1 and T2). The re-
sults did not show significant differences between the two
phases, indicating a stability of the results in the interval of one
year in these patients (Figure 1).
The independent t-test, performed to assess possible differ-
ences between men and women in T1 and T2 concerning the
QoL, self-efficacy and psychological well-being, showed that
in T1 the men had higher levels of the QoL than the women in
the total questionnaire ( t = 2.406; p < .05) and in the physical (t
= 3.021; p < .01) and social relations (t = 1.980; p < .05) di-
Table 2.
Correlations.
QV T1 QVf1 QVp1 QVs1 QVa1 QV T2QVf2QVp2QVs2QVa2AUT-EF B-E AUT-EF2B-E2
QV T1 - .834b .809b.629b .860b .426b .405b.412v.22 .338a .514b –.749b .358a –.452b
QVf2 - .605b.394b .618b .317a .326a.314a.19 .23 .483b –.692b .346a –.362a
QVp2 - .474b .496b .337a .27 .435b.08 .27 .446b –.588b .307 –.236
QVs2 - .421b .392b .386b.27 .472b.27 .300a –.335a .159 –.313a
QVa2 - .349a .345a.292a.14 .308a.391b –.665b .293 –.477b
QV T2 - .829b.793b.485b.947b.027 –.297a .825b –.306a
QVf2 - .596b.2 .740b.119 –.292a .628b –.290a
QVp2 - .25 .641b.129 –.363b .739b –.149
QVs2 - .372b–.129 –.05 .404a –.393b
QVa2 - –.024 –.23 .788b –.245
AUTfEF - –.543
b .1 –.084
B-E - –.291 .569b
AUT-EF2 - –.316
B-E2 -
Abbreviations: QVT1, total quality of life in T1; QVf1, physical quality of life in T1; QVp1, psychological quality of life in T1; QVs1, social quality of life in T1; QVa1,
environmental quality of life in T1; AUT-EF, self-efficacy in T1; B-E, well-being in T1; QV T2, total quality of life in T2; QVf2, physical quality of life in T2; QVp2,
psychological quality of life in T2; QVs2, social quality of life in T2; QVa2, environmental quality of life in T2; AUT-EF2, self-efficacy2; B-E2, well-being2. ap < .05. bp
< .01.
E. K. DE CASTRO ET AL.
Figure 1.
Averages of the total QoL and its dimensions, self-efficacy and psychological well-being in T1 and T2.
mensions and higher indices of psychological well-being
(–2.041; p < .05). In T2, the men also had better indicators of
the QoL than the women, but only in the social relations di-
mension (t = 2.024; p < .05) and in the psychological well-
being (t = –2.341; p < .05). There were no significant differ-
ences between genders in the self-efficacy in T1 and T2.
Linear regression analysis (stepwise method) showed that the
only predictive variable of the QoL in T2 was the self-efficacy
(T2) (β = 0.848, p < .001), which explained 71.9% of the vari-
ance (R2 = 0.719, p < .001).
Discussion
The present study aimed to examine longitudinally (one year)
the QoL, self-efficacy and psychological well-being of patients
with cancer. Generally speaking, the results indicated a relative
stability of these variables during the period investigated. More-
over, the variables measured in T1 were not predictive of the
QoL in T2, only the self-efficacy in T2.
Few studies have looked at the variables investigated in this
research concerning patients with cancer, and, moreover, their
results are not consistent. As they were performed in cultural
contexts differing from that there (Brazil), and with patients at
different stages of the disease and treatment (Kreitler, Peleg, &
Ehrenfeld, 2006; Rottman, Dalton, Christensen, Frederiksen, &
Johansen, 2010), the results displayed here are not fully com-
parable with those found in the international literature. The very
concept of the QoL, besides being subjective, indicates that it is
related to the environment in which the subject is inserted, as it
takes into account the cultural requirements of the location
(Fleck et al., 2000).
The participants of this study, all attended to free of charge
by the Brazilian Unique Health System2, were characterized by
poor schooling and by the heterogeneity of the types of cancer
diagnosed. According to Sprangers et al. (2000), the poor school-
ing may lead the subjects to have difficulty in understanding
and evaluating their own QoL. It was also found in the com-
parative biosociodemographic data between T1 and T2 that the
number of patients with metastasis increased, which indicates
that the disease, at least for this patient group, was not con-
trolled. Considering this issue, the stability of the levels of the
QoL, self-efficacy and psychological well-being can be under-
stood to be a positive result, as, for at least part of these patients,
their state of health was not better in T2 than in T1.
The significant correlations observed between the QoL, self-
efficacy and psychological well-being are congruent with the
result of the stability of these variables in the period of one year.
These findings corroborate other studies (Kreitler, Peleg, &
Ehrenfeld, 2006; Campbell et al., 2004; Rottman, Dalton, Chris-
tensen, Frederiksen, & Johansen, 2010) which found a positive
association between self-efficacy, psychological well-being, the
QoL and mental health. Thus, self-efficacy is associated with
better results in health, as already found in studies with patients
with other types of chronic disease (Scholz, Gutiérrez-Doña,
Sud, & Schwarzer, 2002).
The significant correlations between the QoL and psycho-
logical well-being are also theoretically relevant and expected,
as patients who perceive their life as having greater quality
would be happier. However, one’s attention is drawn to the fact
that in T2 the correlation between psychological well-being and
the psychological dimension of the QoL was not significant.
One hypothesis for this result is that, perhaps, with the adapta-
tion of the patients to coping with the disease, they perceive
their lives as having a reasonable psychological QoL, consider-
ing their suffering and physical limitations, but do not feel
“happy” with this. On the other hand, psychological well-being
was correlated in T2 with the physical and environmental di-
mensions of the QoL possibly because these patients are more
concerned with their disease and with their capacity to adapt to
the environment than with their feelings (psychological dimen-
sion). Other issues could also be related to the QoL and psy-
chological well-being and may be interfering in the non-corre-
lation with the psychological dimension in T2, as the social
support perceived, for example. Future studies will need to
study this issue in greater depth.
One’s attention is also drawn to the differences found in the
levels of the QoL and psychological well-being between men
and women, especially in T1. For Kwan et al. (2010), the psy-
chosocial consequences of cancer is greater for younger than
older women, which can have an impact on their QoL. How-
ever, when dealing specifically with the QoL and psychological
2In Brazil, access to health services is universal (Ministry of Health, 2010).
However, in practice, due to the difficulty of accessing these services and
the precariousness of the attendance in certain sectors, the poorest segment
of the population use them, whereas the middle and up
p
er classes usually
opt for private health plans.
Copyright © 2012 SciRes. 307
E. K. DE CASTRO ET AL.
well-being, there is no evidence which explains these differ-
ences in patients with cancer. Nevertheless, the study of Mrus,
Williams, Tsevat, Cohn and Wu (2005), performed with HIV
positive patients found that women had a poorer QoL than men,
similar to the data of the present study. One possible interpreta-
tion of the results of this study may be related to the psycho-
logical implications of chemotherapy treatment for women,
which produces important collateral effects that affect espe-
cially the female identity, as is the case of alopecia (hair loss).
Hair is associated with the feeling of the woman’s self-concept,
and its loss not only generates changes in her body image, but
also alters her social behavior (Münstedt, Manthey, Sachsse,
Vahrson, & Changes, 1997). Besides chemotherapy, some types
of surgery also have an impact on the self-image, the female
identity and possibly on her QoL, as is the case of mastectomy
for treatment of breast cancer or hysterectomy for the treatment
of cancer of the uterus (Silva, 2008). Thus, the corporal trans-
formation caused by the disease and by the treatment in the
woman may be stronger than in the man, leading to a reduction
of her social contact and, consequently, of the quality of her
social life. In this respect, bearing in mind that the participants
of the study included several women with breast cancer, a type
of neoplasia directly related to female issues, the gender differ-
ences found here may be due to this reason.
The fact that we did not find any significant differences in
self-efficacy between men and women seems to make sense as
it can be considered to be a personal resource particular to each
subject (Bandura, 1997, 2001). Self-efficacy, according Ban-
dura, provides indicators about the individual’s long-term ad-
aptation, including regarding his/her health. In this respect, it is
possible to instigate psychological interventions in the context
of health which can aid the patients to adapting to and coping
with the disease (Rottman, Dalton, Christensen, Frederiksen, &
Johansen, 2010).
Another result which is worthy of note is the difference
found between male and female patients in T1 and T2 in the
quality of social life, indicating better results for men. Taking
into account that the woman’s self-image can be greatly im-
pacted by the treatment (Münstedt, Manthey, Sachsse, Vahrson,
& Changes, 1997), it is possible that the poor quality of social
life of these women is related to the shame or fear of being seen
without hair or with the body mutilated. For the man, the loss
of hair is regarded as normal, as when they get old they become
bald. This may be contributing to a difference in the QoL be-
tween the genders to the extent that the women end up reducing
their social contact.
Although the study has shown that the men also perceived
themselves with better psychological well-being in T1 and T2
than the women, in the other variables this difference was not
significant. This data indicates that the men were close in the
levels of the QoL and self-efficacy to the women, although
some differences also remained. It may be that men and women
assimilate the diagnosis and treatment of cancer at different
times, and so with the passage of time their well-being and QoL
could be getting closer to each other.
The participants of this study were young and may be part of
a group of patients especially affected by a chronic disease such
as cancer (Kwan et al., 2010; Semiha, Can, Durna, & Aydiner,
2008), as they are at the apex of their life (career development,
forming a family, etc.). Thus, the impact of the cancer upon
their QoL may also be particularly important. However, these
findings may be not applied for older patients. Future studies
with Brazilian samples will be able to compare the existence of
differences in the QoL of patients who are young, middle-aged
and senior citizens diagnosed as having cancer.
The findings of this study showed a close relationship be-
tween the QoL, perception of self-efficacy and psychological
well-being, and that in the period of one year they remained
relatively stable in the participants of this study. Moreover, the
differences found between men and women indicate possible
psychological vulnerability of women regarding the disease.
Considering that cancer is a disease which can greatly alter the
QoL of patients, it is necessary to make further studies starting
from these gender differences. Investigating issues related to
the performance of the female and male role in the situation of
a chronic disease regarding the family and society becomes
necessary in order to understand the phenomenon raised ere
more fully.
This study has limitations, such as, for example, the hetero-
geneity of the sample related to the types of cancer, particulari-
ties which could not be assessed in this study. Nevertheless, the
results found here offer a first portrait of the situation of young
Brazilian patients with cancer, and can be used as a point of
departure for further studies about the subject.
REFERENCES
Bandura, A. (1997). Self-efficacy: The exercise of control. New York:
W. H. Freeman and Company.
Bandura, A. (2001). Social cognitive theory: An agentic perspective.
Annual Review of Psychology, 52, 1-26.
doi:10.1146/annurev.psych.52.1.1
Bertan, F. C., & Castro E. K. (2009). Quality of life and câncer: A
systematic literature review. Psico, 40, 366-372.
Campbell, L. C., Keefe, F. J., Mckee, D. C., Edwards, C. L., Herman, S.
H., Johnson, L. E., Colvin, O. M., McBride, C. M., & Donatucci, C.
F. (2004). Prostate cancer in African Americans: Relationship of pa-
tient and partner self-efficacy to quality of life. Journal of Pain and
Symptom Management, 28, 433-444.
doi:10.1016/j.jpainsymman.2004.02.020
Fleck, M., Louzada, S., Xavier, M., Chachamovich, E., Vieira, G.,
Santos, L., & Pinzon, V. (2000). Application of the Portuguese
version of the abbreviated instrument of quality life WHOQOL-bref.
Revista de Saúde Pública, 34, 178-183.
doi:10.1590/S0034-89102000000200012
Goldberg, D. P. (1978) Manual for the general health questionnaire.
Windsor: National Foundation for Educational Research;.
Gouveia, V., Chaves, S. S. da S., Oliveira I. C. P. de, Dias, M. R.,
Gouveia, R. S. V., & Andrade, P. R. de. (2003). The use of the
GHQ-12 in a general population: a study of its construct validity.
Psicologia: Teoria e Pesquisa, 19, 241-248.
doi:10.1590/S0102-37722003000300006
Howell, R. T., Kern, M. L., & Lyubomirsky, S. (2007). Health benefits:
Meta-analytically determining the impact of well-being on objective
health outcomes. Health Psychology Review, 1, 83-136.
doi:10.1080/17437190701492486
Kreitler, S., Peleg, D., & Ehrenfeld, M. (2006). Stress, self-efficacy and
quality of life in cancer patients. Psycho-Oncology, 4, 329-341.
Kwan, M. L., Ergas, I. J., Somkin, C. P., Charles, P., Quesenberry, C. P.
Jr., Alfred, Neugut, A. I., Hershman, D. L., Mandelblatt, J., Pelayo,
M. P., Timperi, A. W., Miles, S. Q., & Kushi, L. H. (2010). Quality
of life among women recently diagnosed with invasive breast cancer:
The Pathways Study. Breast Cancer Research and Treatment, 123,
507-524. doi:10.1007/s10549-010-0764-8
Mayo, N. E., Moriello, C., Asano M., Van der Spuy, S., & Finch, L.
(2011). The extent to which common health-related quality of life
indices capture constructs beyond symptoms and function. Quality of
Life Research, 20, 621-627. doi:10.1007/s11136-010-9801-7
Montazeri, A. (2008). Health-related quality of life in breast cancer
Copyright © 2012 SciRes.
308
E. K. DE CASTRO ET AL.
Copyright © 2012 SciRes. 309
patients: A bibliographic review of the literature from 1974 to 2007.
Journal of Experimental & Clinical Cancer Research, 29, 27-32.
Mrus, J. M., Williams, P. L, Tsevat, J., Cohn, S. E., & Wu, A. W.
(2005). Gender differences in health related quality of life in patients
with HIV/Aids. Quality of Life Research, 14, 479-491.
doi:10.1007/s11136-004-4693-z
Münstedt, K., Manthey, N., Sachsse, S. & Vahrson, H. (1997). Changes
in self-concept and body image during alopecia induced cancer che-
motherapy. Supportive Care in Cancer, 5, 139-143.
doi:10.1007/BF01262572
Perkins, H. Y., Baum, G. P., Taylor, C. C., & Basen-Engquist, K. M.
(2009). Effects treatment factors, comorbidities and health-related
quality of life on self-efficacy for physical activity in cancer survi-
vors. Psycho-Oncology, 18, 405-411. doi:10.1002/pon.1535
Ramachandra, P., Booth, S., Pieters, T., Vrotsou, K., & Huppert, F. A.
(2009). A brief self-administered psychological intervention to im-
prove well-being in patients with cancer: Results from a feasibility
study. Psycho-Oncology, 18, 1323-1326. doi:10.1002/pon.1516
Rottman, N., Dalton, S. O., Christensen, J., Frederiksen, K., &
Johansen, C. (2010). Self-efficacy, adjustment style and well-being
in breast cancer patients: A longitudinal study. Quality of Life Re-
search, 19, 827-836. doi:10.1007/s11136-010-9653-1
Seidl, E. M. F., & Zannon, C. M. C. (2004). Quality of life and health:
Conceptual and methodological issues. Cadernos de Saúde Pública,
20, 580-588. doi:10.1590/S0102-311X2004000200027
Semiha, A., Can, G., Durna, Z., & Aydiner, A. (2008). The quality of
life and self-efficacy of Turkish breast cancer patients undergoing
chemotherapy. European Journal of Onc ology Nu rsing, 12, 449-456.
doi:10.1016/j.ejon.2008.07.006
Scholz, U., Gutiérrez-Doña, B., Sud, S., & Schwarzer, R. (2002). Is
general self-efficacy a general construct? Psychometric findings from
25 countries. European Journal of Psychological Assessment, 18,
242-251. doi:10.1027//1015-5759.18.3.242
Schwarzer, R., Boehmer, S., Luszczynska, A., Mohamed, N. E., &
Knoll, N. (2005). Dispositional self-efficacy as a personal resource
factor in coping after surgery. Personality and Individual Differences,
39, 807-818. doi:10.1016/j.paid.2004.12.016
Silva, L. C. (2008). Breast cancer and psychological suffering: Female-
related aspects. Psicologia em Estudo, 13, 231-237.
doi:10.1590/S1413-73722008000200005
Sprangers, M. A. G., Regt, E. B., Andries, F., Van Agt, H. M., Boer, J.
B. de., Foets, M., Hoevmans, N., Jacobs, A. E., Kempen, G. I.,
Miedema, H. S., Tijhuls, M. A., & De Haes, H. C. (2000). Which
chronic conditions are associated with better or poorer quality of life?
Journal of Clinical Epidemiology, 53, 895-907.
doi:10.1016/S0895-4356(00)00204-3
Teixeira, M. A., & Dias, A. C. (2005). Psychometric properties of Por-
tuguese version of Perceived self-efficacy by Ralph Schwarzer. Em
Resumos do II Congresso Brasileiro de Avaliação Psicológica [CD].
Instituto Brasileiro de Avaliação Psicológica (Org.): Gramado: IBAP.