Introduction
Cancer is a common and important health problem
worldwide. As stated by the World Health Organization
(WHO), 9.6 million people died due to cancer
only in 2018.[] According to the data published by
the WHO in 2018, 210 thousand 537 new cases of cancer
were reported in Turkey.[] According to the Turkish
Ministry of Health data, an average of 163 thousand
cancer cases is reported every year in Turkey. In
2015, 177 out of every 100 thousand women and 247 out of every 100 thousand men were diagnosed with
cancer.[] According to the World Cancer Research
Fund (WCRF) data, the most common cancer types
in the world in 2018 were lung cancer, breast cancer,
and intestinal cancer, respectively.[] Breast cancer is
the second most common cancer in women and the
second most common cancer worldwide. There were
more than 2 million new cases in 2018. The WCRF reported
that breast cancer is most common in Australia
(468/100 thousand), followed by New Zealand (373)
and Ireland (438).[] In Turkey, one in every four female cancer patients has breast cancer.[] When the
age distribution of breast cancer in Turkey is analyzed,
it is seen that the age group in which breast cancer is
the most common is the 25-49 age group with 34.2%,
compared to other age groups.[]
Although breast cancer mortality rates decrease in
many high-income countries, incidence and mortality
rates increase especially in fast-developing countries.
[] This increase is associated with changes in lifestyle,
changes in reproductive functions, nutritional habits,
population growth, aging, and the increase in screening
methods.[,] The WHO stated that cancer cases
can be prevented by controlling environmental conditions
and through age changes. The WHO emphasizes
that the most cost-effective long-term strategy for cancer
control is cancer prevention and at least one-third
of all cancer cases are preventable.[] It is estimated
that 30-50% of cancer cases can be prevented by avoiding
risk factors and implementing evidence-based prevention
strategies.[] Ensuring public awareness about
cancer, developing community awareness and cancer
screening are among the most effective methods in the
fight against cancer. In Turkey, cancer screening is carried
out as recommended by the WHO. In 2014, the
standards to be followed during the community-based
breast cancer screening program studies were redefined
by the Public Health Institution of the Ministry
of Health and published under the title "The National
Standards of the Breast Cancer Screening Program."
Accordingly, it has been acknowledged that screening
mammography be carried out among all the women
aged 40-69 years every 2 years. In an effective screening
program, it is aimed that more than 70% of the target
population participate in the screening. To create social
awareness, it has been recommended to give consultancy
service to every woman above 20 years of age
to perform breast examination on their own.[] Within
the scope of the breast cancer screening program, consultancy
service is provided to women so that they
do Breast Self-Examination (BSE) monthly, women
between the ages of 40 and 69 years undergo clinical
breast examination once a year and mammography
once in 2 years.[] In 2018, 34.8% of the women in
Turkey had mammography. This rate is quite low compared
to many European countries.[] To implement
screening programs, raising awareness od breast cancer
among women is essential.
Breast cancer incidence in Turkey was reported to be
24/100.000 in 1993, while it increased to 50/100.000 in
2017, indicating a more than double increase.[] Delayed
breast cancer diagnosis in developing countries may be related to poor breast cancer awareness and barriers
to access to health-care services.[-] Breast cancer
awareness is not strong. Particularly low levels of education
in women, socio-cultural characteristics and belief
systems, including fatalism and moral reasons, may
affect awareness.[-] Low health literacy levels pose
an important obstacle that affects screening attitudes for
breast cancer knowledge and the source of information
among women.[] Despite increasing screening centers
and free mammography (40-69 years) and mobile
screening systems in recent years, a significant number
of patients in Turkey are diagnosed at an advanced stage
due to the lack of breast cancer awareness.[]
Increasing breast cancer awareness is considered as
the first step in both primary and secondary prevention
and commonly in the fight against breast cancer. It is
important to understand and improve the level of breast
cancer awareness.[] The first step of breast cancer
awareness is the availability of valid and reliable tools
that measure this construct and the related factors. Appropriate
interventions can be designed and evaluated
to increase breast cancer awareness even with only such
tools. Various tools have been proposed to evaluate
breast cancer awareness.[-] As a result of the literature
review, no accepted measurement toolhas been
found to evaluate breast cancer awareness in Turkey.
Thus, this study aimed to evaluate the validity and reliability
of the Breast Cancer Awareness Scale (B-CAS)
to determine the level of awareness about breast cancer.
Methods
Research Type
The B-CAS was developed by Rakkapao et al. (2016)
for the early diagnosis and prevention of breast cancer.
It is easy to use and was designed as a self-report
tool that allows researchers and practitioners to better
understand women"s awareness level of breast cancer.
The original scale consists of five factors and 35 items.
The factors are Knowledge of Risk Factors, Knowledge
of Signs and Symptoms, Attitude to Breast Cancer
Prevention, Barriers of Breast Screening, and Health
Behavior related to Breast Cancer Awareness. This
study is a methodological study. Turkish validity and
reliability of the B-CAS were tested.
The Research Context and its Characteristics
The study was carried out in a Family Health Center in
Konya. In the Family Healthcare system, women of all
ages are integrated into the system. Women receive counseling
through invitation, and their health check is done.
Research Population and Sample Size
All the women in the 20-69 age group registered in
the family health system constituted the research population.
In Turkey, breast cancer is among the most
common cancer types in women. After 20 years of
age, women receive counseling for BSE and women
between the ages of 40 and 69 are scanned for breast
cancer through the invitation method every 2 years.
[] Based on this data, all women between the ages of
20 and 69 registered in the family health system constituted
the research population. In validity and reliability
studies, it is suggested that sample size should be 5-10
times of the number of items so that analyses could be
carried out.[-] Since there are 35 items in the BCAS,
it was determined that there should be at least
350 people, which is 10 times higher than the number
of items.
Research Inclusion Criteria
The following criteria were included in the study:
• Having no diagnosed disease related to breast
• Being literate in Turkish
• Having no psychiatric problems (to be determined
based on self-report).
Research Exclusion Criteria
The following criteria were excluded from the study:
• Having been diagnosed with breast cancer
• Being illiterate.
Data Collection Technique and Tools
The Personal Information Form and the B-CAS were
used to collect data. The Personal Information Form
consists of 12 questions including the socio-demographic
characteristics of women. The questions are
related to participants" age, educational status, employment
status, monthly income, marital status, number
of children, having experienced menopause or not,
first menstrual age, being a smoker or not, cancer history
in the family, etc.
The B-CAS was developed by Rakkapao et al.
(2016) for the early diagnosis and prevention of breast
cancer. The scale consists of five factors and 35 items.
The five factors are Knowledge of Risk Factors, Knowledge
of Signs and Symptoms, Attitude to Breast Cancer
Prevention, Barriers of Breast Screening, and Health
Behavior related to Breast Cancer Awareness. In the
scoring of the scale, Knowledge of Risk Factors and
Knowledge of Signs and Symptoms factors are marked
as "Yes," "I do not know," and "No" In scoring, 2 points
are received for the correct answer, 1 point is received for the answer "I do not know," and 0 point is received
for the wrong answer. The factors of Attitude to Breast
Cancer Prevention, Barriers of Breast Screening, and
Health Behavior related to Breast Cancer Awareness
are scored on a five-point Likert scale as 1 point for
"strongly disagree" and 5 points for "strongly agree."
The study is composed of two stages. At the first
stage, the scale was translated from English to Turkish
to ensure language validity, and translation validity
was tested. For this purpose, first of all, permission was
obtained from the developers of the scale to carry out
the Turkish validity and reliability study. The translation
of the scale was made by experts who know both
languages and know how to use the scale. The scale was
first translated into Turkish by two experts who are
experts in their fields and proficient in English. It was
checked whether these two translations matched.
Content validity is concerned with examining to
what extent the scale measures the construct that is intended
to be measured. If the developed test includes all
the important subtopics of the subjects that are examined,
it is accepted that the test has content validity. It is
recommended to seek expert opinion for this purpose.
The expert group should consist of at least three and
at most 20 people.[] Experts are asked to evaluate
whether the items produced represent the construct to
be measured, whether the items are sufficiently simple
and clearly expressed, and whether they are expressed
appropriately for the target audience. Content Validity
index (CVI) is used to prove content validity with numerical
values. For this evaluation, experts are asked to
score each scale item between 1 and 3.
1 point: Not appropriate
2 points: The item needs to be revised
3 points: Appropriate.
Evaluation: (Number of experts who say the item is
necessary/[Total number of experts/2]-1).
If the scale has two or more dimensions, CVI must
be calculated separately for each dimension. For the
scale to have content validity, the CVI score must be
0.80 and above.[]
Construct Validity
Construct validity is concerned with to what extent abstract
concepts, which cannot be directly observed, are
measured correctly, to what extent the goal is achieved,
and how accurately it has been measured. There are
four methods to evaluate construct validity: Factor
analysis, the comparison of opposite or known groups,
hypothesis testing, and multivariate multi-method matrix
method. In this study, the factor analysis method was used. Factor analysis is a statistical method that
allows to combine a large number of related variables
and to express them with fewer new variables.[,]
Factor analysis consists of two parts: Exploratory and
confirmatory factor analysis.[,] In our study, exploratory
factor analysis was used.[]
Exploratory factor analysis is a method used to reveal
under how many sub-headings the items in the
scale will be grouped and how these groups relate to
each other.[] The sample size should be sufficient
for exploratory factor analysis, and there are various
opinions on this. While some say the sample size
should be 5 or 10 times the number of items in the
scale, others say sample size should be three to five
hundred people.[] The Kaiser-Meyer-Olkin (KMO)
measure of sampling adequacy was used to determine
that the sample size was adequate. As the value obtained
at the end of this measure approaches 1, sampling
adequacy increases, whereas if the value moves
away from 1, sampling adequacy decreases. According
to some researchers, sample size of at least 0.60 is
adequate, while for others, it should be 0.80. Sample
size between 0.80 and 0.90 is generally considered to
be very good, while sample size over 0.90 is considered
to be excellent. For the exploratory factor analysis,
first, KMO, which tests the suitability of the data
set for factor analysis, and the Bartlett Test, which
examines the correlation between the variables, were
applied.[] A valid test should also be reliable. Thus,
the internal consistency reliability test was performed
to determine whether all aspects of the scale are capable
of measuring. For this purpose, Cronbach's Alpha
Reliability coefficient and Total Item Score Scale reliability
Kappa fit coefficient were examined.
Ethical Considerations
The participants were informed both verbally and
in writing about the study and were included after
providing their informed consent in compliance with
the Helsinki Declaration. Ethics committee approval
was obtained from Necmettin Erbakan University,
Meram Medical Faculty Hospital, Clinical and Non-
Pharmaceutical Research Ethics Committee. For
validity and reliability scale necessary permits were
obtained from the owner Dr. Cameron Hurst. Necessary
permissions were also obtained from the administrators
of the Family Health Center, where the study
was conducted. In addition, after giving detailed information
about the research to women who would
participate in the study, their written and verbal consent
was obtained.
Limitations
The research is limited to the answers given only by the
participants.
Statistical Analysis of the Data
The SPSS and AMOS software programs were used for
the statistical analysis of the data.
Results
In this study, the psychometric properties of the B-CAS
were tested for Turkish sample. The original scale has
five dimensions which are Knowledge of Risk Factors,
Knowledge of Signs and Symptoms, Attitude to Breast
Cancer Prevention, Barriers of Breast Screening, and
Health Behavior related to Breast Cancer Awareness.
The first two dimensions include questions with "Yes-I
do not know-No" options, while the other three dimensions
include questions that are evaluated on a
five-point Likert scale from "1 - I strongly disagree" to
"5 - I strongly agree."
Participant Characteristics
The average age of the participants was found to be
34.68±10.90 (Table 1).
Table 1: Demographic characteristics of the participants
Language and Content Validity Analysis
To ensure language equivalence, the original scale was
translated from English to Turkish by a language expert
who knew and understood both languages well, and the
translated statements were back- translated to English
by another language expert. Three academicians who
are experts in both languages evaluated whether there
was any meaning loss in the translated version compared
to the original scale. During this evaluation, the
items in the scale were compared and language validity
was assessed by checking the integrity of meaning.
Validity is an important criterion for the credibility
and generalization of the study.[,] In validity
studies, it is important that the correlation between
the scale to be developed and what is intended to be
measured is consistent. This is called content validity,
through which how much each item serves the purpose
is determined. With this method, the items that best inrepresent
the research topic can be determined from
among the items in the scale and irrelevant items can
be excluded.[,-] Different techniques have been
developed to test content validity.[-] One of the
most widely used techniques is the technique developed
by Lawshe (1975).[,] This technique is both
simple and useful.[]
In this study, first, the expert group was created,
the initial scale was prepared, and expert opinions
were obtained. Then, the content validity ratios (CVR)
were calculated with the data obtained. The quality and
number of experts (between 5 and 40) are important
to assess content validity.[,,,] In this study,
opinions of 11 experts were received. The expert form
included the 35 items to determine content validity.
The experts were asked to mark one of the alternatives
(1 - The item is not appropriate, thus it needs to be
removed from the scale; 2 - The item is appropriate,
but needs to be revised; and 3 - The item is appropriate)
to evaluate the items in the expert form. In Lawshe
(1975) technique, expert opinions for each item
are rated as "the item measures the target construct,"
"the item is related to the construct, but not essential"
and "the item does not measure the target construct."
In this study, the items were scored as "Appropriate" 3
points, "Appropriate but should revised" 2 points, and
"Not necessary" 1 point. In addition to the rating in the
Lawshe (1975) technique, if the experts have selected
the option, the researchers also asked the following
questions to the experts: "If your response is "Appropriate
but should revised," what is your suggestion?"
and "If your response is "Not necessary," why do you
think the item is not essential?"
In this study, it was decided to take the values of
CVR proposed by Ayre and Scally (2014) as the basis.
The CVR is calculated by dividing the number of experts
who classify an item as "essential" (E) by the total
number of experts divided by 2 (N/2) and subtracting
1 from the resulting number ([E/[N/2]]-1). This calculation
is made for each item and it is evaluated whether
the item is suitable considering the value in the table
calculated according to the number of experts.[]
Ayre and Scally (2014) reported that the critical value
of CVR should be 0.636 for 11 experts. CVI is the average
of the CVR value of the items left in the pool. In
addition, some grammatical and spelling errors in the
scale were corrected. Most of the items were scored as
"appropriate" by the experts and the CVI was found to
be 0.93 (Table 2). In line with the suggestions of the
experts, the integrity of the expressions was ensured in
the scale items. The content validity of the scale was completed by piloting the final version of the scale in a
group of 15 people in terms of readability and understandability
in Turkish.
Table 2: Expert opinion content validity index calculation
Construct Validity
Before the scale"s construct validity, KMO value and
Bartlett"s test results were examined. KMO was determined
as 0.76, and Bartlett"s test result was X2=6411.088.
Both test results were found at p=0.00 significance level.
Within the scope of this study, the factor structure of
the scale was analyzed using the principal components
analysis and the KMO value was found to be 0.76. As
a result of the analysis, 11 factors with eigenvalues >1
and explaining 71.73% of the variance were obtained.
However, since the items in these factors did not constitute
a meaningful structure, the scale was forced to a
5-factor structure and the analyses were repeated, based
on the factor analysis results of the original scale and the
analysis proposed in the scree-plot graph. After the Varimax
axis rotation, a 5-factor structure, which explained
50.33% of the variance and had factor loadings ranging
from 0.30 to 0.81, was obtained. When the factors under
which the items were loaded were analyzed, it was seen
that the item "The history of breast cancer in the family"
was under the Knowledge of Risk Factors Factor in
the Original Scale; however, in this study, it was loaded
on the factors of both Knowledge of Risk Factors and
Knowledge of Signs and Symptoms. It was decided to
exclude the item from the analyses since the difference
between the loadings on two factors was <0.10. Furthermore,
the item "How many days a week do you eat fresh
vegetables?" under the Health Behavior related to Breast
Cancer Awareness dimension was found to have a factor
loading below 0.30, and the items "How many days
a week do you exercise or do sports?" "Have you heard
about the breast screening policy of the health-care personnel
in your neighborhood?" "How often do you have
clinical breast screening?" and "How often do you have
mammography?" were found to have corrected total
item correlation values below 0.30; thus, all these items
were removed from the analyses. After the six items
were removed, the analyses were repeated.
As a result of repeated analyses, a five-factor structure,
which explained 57.85% of the variance and had
factor loadings ranging from 0.63 to 0.82, was obtained.
All the items in the structure obtained were found to be
compatible with the original scale. In addition, it was
observed in the research sample that the sub-dimensions
of the scale had good internal consistency. The
total Cronbach Alpha internal consistency coefficient
of the scale was calculated as 0.71. Cronbach Alpha internal consistency coefficients of the sub-dimensions
of the scale were calculated as 0.87 for the Knowledge
of Risk Factors dimension, 0.88 for the Knowledge of
Signs and Symptoms dimension, 0.81 for the Attitude
to Breast Cancer Prevention dimension, 0.78 for the
Barriers of Breast Screening dimension, and 0.61 for
the Health Behavior related to Breast Cancer Awareness
dimension. The factor loadings of the scale items,
the eigenvalues of the obtained structures and the variance
values explained are presented in Table 3, while
the corrected total item correlation for the items under each factor and the Cronbach Alpha value of the scale
if the item is deleted are presented in Table 4.
Table 3: Exploratory factor analysis results of breast cancer awareness scale
Table 4: Corrected item total correlation values for scale items and cronbach alpha values of the scale if the item is deleted
In this study, correlations between factors were also
examined. The results revealed that there is a positive
relationship between the dimensions of Knowledge
of Signs and Symptoms, Knowledge of Risk Factors,
and Barriers of Breast Screening. On the other hand,
the Attitude to Breast Cancer Prevention dimension
was found to have a negative relationship with the dimensions
of Knowledge of Signs and Symptoms and
Knowledge of Risk Factors. Furthermore, a negative relationship was revealed between the Barriers of Breast
Screening and the Health Behavior related to Breast
Cancer Awareness dimensions (Table 4, 5).
Table 5: Correlations between factors
Discussion
With this study, the validity and reliability analyses of
the B-CAS were made and the scale was adapted to be
used in the Turkish context. The B-CAS is the first tool
known in Turkey to assess the awareness of breast cancer
among women. The analyses revealed that the BCAS
is a valid and reliable tool.
In our study, as a result of the analysis of the factors
under which the items were loaded, it was determined
that there was 1 item that was loaded on both factors and
5 items whose loadings were not sufficient. After these
6 items were removed from the scale, the analyses were
repeated. As a result of the repeated analyses, a five-factor
structure, which explained 57.85% of the variance
and had factor loadings ranging from 0.63 to 0.82, was
obtained. When the factors under which the items were
loaded were analyzed, it was seen that the item "The
history of breast cancer in the family" is under the dimension
of Knowledge of Risk Factors in the original scale; however, in our study, the item was loaded on the
factors of both Knowledge of Risk Factors and Knowledge
of Signs and Symptoms. Similarly, it was observed
that there were problems about the same item in the original scale[] and in the study of Solikhah et al.
(2017).[] In our study, the items "How many days a
week do you eat fresh vegetables?" "How many days a
week do you do exercise or sports?" "Have you heard about the breast screening policy of the health-care
personnel in your neighborhood?" "How often do you
have clinical breast screening?" and "How often do you
have a mammography?" in the Health Behavior related
to Breast Cancer Awareness dimension were removed
from the scale. In the study of Solikhah et al. (2017), the
items "How often do you eat dessert" and "How often
do you eat high-fat chicken, beef or duck meat" were removed.
According to our findings, of the 35 items in the
original scale, 29 items were kept in the Turkish scale.
In the study of Solikhah et al.[] (2017), 33 items of
the original scale were included in the new scale. In our
study, it was thought that it was more appropriate to
remove the items with inappropriate loadings. All the
items under the factors showed a distribution similar to
the factors in the original scale.[]
The total Cronbach Alpha internal consistency coefficient
of the scale was calculated as 0.71 in our study.
The total Cronbach Alpha coefficient of the original
scale was found to be 0.86,[] while it was calculated
as 0.79 in the study of Solikhah et al.[] (2017). The
Cronbach Alpha internal consistency coefficients of
the sub- dimensions of the scale are 0.87 for Knowledge
of Risk Factors, 0.88 for Knowledge of Signs and
Symptoms, 0.81 for Attitude to Breast Cancer Prevention,
0.78 for Barriers of Breast Screening, and 0.61 for
Health Behavior related to Breast Cancer Awareness.
The scale showed good internal consistency in accordance
with the original version administered to Thai
women (?=0.86, factor score=0.71-0.83).[]
Our results revealed a positive relationship between
the dimensions of Knowledge of Signs and Symptoms,
Knowledge of Risk Factors, and Barriers of Breast
Screening. The dimension of Attitude to Breast Cancer
Prevention was found to be negatively correlated with
the dimensions of Knowledge of Signs and Symptoms
and Knowledge of Risk Factors. The Barriers of Breast
Screening dimension was found to be negatively correlated
with the Health Behavior related to Breast Cancer Awareness dimension. In the study of Solikhah
et al.[] (2017), while the Knowledge of Risk Factors
subscale was positively correlated with the subscales of
Knowledge of Signs and Symptoms, Attitude to Breast
Cancer Prevention, and Health Behavior related to
Breast Cancer Awareness; the subscale of Attitude to
Breast Cancer Prevention was found to have a negative
relationship with the Health Behavior related to Breast
Cancer Awareness subscale.
Conclusion
In this study, the validity and reliability of the B-CAS
were tested by adapting it to Turkish. The analyses revealed
that the validity and reliability of the Turkish
form of the scale was sufficient. The Turkish version of
the B-CAS, including 29 items, can be used as a valid,
reliable, and easy-to-use self-report measurement tool
in the assessment of women"s breast cancer awareness.
The scale can contribute to the development and evaluation
of appropriate educational interventions to
increase breast cancer awareness in Turkish women.
Future studies should focus on verifying the B-CAS in
addition to evaluating construct and criterion validity.
Peer-review: Externally peer-reviewed.
Conflict of Interest: The authors declare that they have no
conflict of interest.
Ethics Committee Approval: The study was approved by
the Necmettin Erbakan University, Meram Medical Faculty
Hospital, Clinical and Non-Pharmaceutical Research Ethics
Committee (No: 2018/1540, Date: 26/10/2018).
Financial Support: The authors declared that this study has
received no financial support.
Authorship contributions: Concept - V.K.; Design - V.K.,
K.A.; Supervision - E.E.; Funding - V.K., K.A., E.E.; Materials
- K.A., E.E.; Data collection and/or processing - V.K.; Data
analysis and/or interpretation - V.K., K.A.; Literature search
- V.K., K.A.; Writing - V.K., K.A., E.E.; Critical review - E.E.
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