Illness perception, diabetes knowledge and self-care practices among type-2 diabetes patients: a cross-sectional study
Kugbey et al. BMC Res Notes
Illness perception, diabetes knowledge and self-care practices among type-2 diabetes patients: a cross-sectional study
Nuworza Kugbey 0
Kwaku Oppong Asante 1 2
Korkor Adulai 3
0 Department of Family and Community Health, School of Public Health, University of Health and Allied Sciences , Hohoe, Volta Region , Ghana
1 Discipline of Psychology, School of Applied Human Sciences, University of KwaZulu-Natal , Durban , South Africa
2 Department of Psychology, School of Social Sciences, University of Ghana , Legon, Accra , Ghana
3 Department of Behavioral and Social Sciences, School of Public Health, University of Ghana , Legon, Accra , Ghana
Background: Self-care practices among persons living with type-2 diabetes are very crucial in diabetes manages as poor self-care results in complications. However, little research exists within the Ghanaian context. This study examined whether type-2 diabetes patients' illness perception and diabetes knowledge significantly predict diabetes selfcare practices. Methods: A cross-sectional survey design was employed and a total of 160 participants (45 males and 115 females) were sampled from a general hospital in Accra. A self-administered questionnaire measuring illness perception, diabetes knowledge and diabetes self-care practices as well as demographic checklist were used collect data. Results: Results showed that illness perception and diabetes knowledge significantly predicted overall diabetes selfcare practices. Analysis of domain specific self-care practices showed that patients' diet was significantly predicted by illness perception and diabetes knowledge. Exercise was significantly predicted by only illness perception while blood sugar testing and diabetes foot-care were significantly predicted by diabetes knowledge. Conclusion: Cognitive and emotional representation of diabetes and diabetes knowledge are key determinants of patients' diabetes self-care practices. It is therefore important that appropriate psychosocial interventions are developed to help patients' adherence to recommended self-care practices.
Type-2 diabetes; Self-care practices; Illness perception; Diabetes knowledge
The prevalence of chronic non-communicable diseases
is on the increase within the Sub-Saharan region with
its attendant health, economic and social problems [
]. The rate of type-2 diabetes is said to be high in Africa
with most cases remaining undiagnosed . The case is
not different in Ghana as a developing country where
there is a significant diabetes burden [
]. The situation
requires identification of possible intervention measures
from multiple levels to provide optimum healthcare to
persons who are already living with diabetes.
Effective self-management of type-2 diabetes mellitus
(T2DM) is crucial to reduce the risk of diabetes-specific
complications, such as hypertension, amputation,
nephropathy, neuropathy, retinopathy, cardiovascular
disease, impotence, and skin lesions [
Self-management activities include adherence to diet and nutrition
advice, physical activity, taking mediations as prescribed,
and weight and stress management [
suggests that there is poor adherence to self-care practices
among diabetes patients globally [
]. Thus, it has become
necessary to identity factors that play significant roles in
influencing the T2DM patients’ adherence to self-care
Illness perception has been identified in some
studies as a significant factor that influences self-care
practices, psychological distress and other health outcomes
among persons living with T2DM [
association between illness perception and the health outcomes
could be due to the fact that engagement in self-care
practices involves complex decision making which
depends on the patients’ representation of their illness
in terms of whether it is controllable, comprehensible,
curable, cyclical and severe or not. However, it has been
observed among a sample of Ghanaians living with
diabetes that their overall illness perception influences their
level of psychological distress [
]. Further evidence has
suggested a strong link between diabetes perception and
self-care practices [
]. For example, Broadbent et al.
] found that patients’ diabetes perceptions influence
their adherence to medication, diet and exercise.
Similarly, illness perception domains predict
self-management practices of individuals living with diabetes in the
Diabetes knowledge has been identified as one of the
key determinants of adherence to diabetes self-care
practices. This association is very crucial to diabetes
intervention as both diabetes knowledge and self-care
practices are significantly associated with glycemic
control- a measure of diabetes outcome [
Knowledge about the illness is likely to inform patients about
specific actions in the diabetes management process.
Thus, the more knowledge patients have about their
illness, the more likely they are to comprehend their illness
and take up self-care behaviors such as diet, exercise and
blood sugar testing among others.
Diabetes health literacy which is an indication of
knowledge has been shown to affect self-care practices
among persons living with diabetes [
]. In their study,
van der Heide et al. [
] examined the mediating role of
diabetes knowledge on the relationship between diabetes
health literacy and self-care practices found that lower
health literacy was significantly associated with less
diabetes knowledge, higher glycated hemoglobin (HbA1c)
level, less self-control of glucose level, and less physical
activity. The same study also found that patients with
more diabetes knowledge were less likely to smoke and
more likely to control glucose levels, and that diabetes
knowledge mediated the association between health
literacy and glucose self-control and between health literacy
and smoking [
]. This study emphasized the importance
of diabetes knowledge in self-care practices as it
demonstrated both direct and indirect effects on self-care
practices. Previous studies conducted with persons
living with diabetes in United States and Netherlands also
found possible relationships between diabetes knowledge
and self-care behaviors [
Despite all these evidence suggesting that the diabetes
knowledge has a significant influence on self-care
practices and other health outcomes of persons living with
T2DM, sparse research exists on how self-care practices
of Ghanaians living with T2DM are influenced by their
illness perception and diabetes knowledge. Furthermore,
findings of the influence diabetes knowledge and
illness perception on self-care practices as reported from
developed countries cannot necessarily be adduced to
diabetes patients living in Ghana. This study was
therefore conducted to examine whether self-care practices of
persons living with T2DM are significantly predicted by
their illness perception and diabetes knowledge. The
outcomes from this study may inform interventions aimed
at promoting optimum health outcomes of persons living
Two key models underpin this study, the health belief
model and the self-regulation model [
models were used to examine how illness perception and
diabetes knowledge influence the self-care practices of
persons living with type-2 diabetes in Ghana. These two
models overlap in explaining self-care practices,
however, the self-regulation model  was used to explain
how illness perception influence diabetes self-care among
the participants. The self-regulation model developed by
Leventhal, Meyer and Nerenz [
] posits that when
individuals are faced with threatening situations like
chronic illnesses, they tend to generate both emotional
and cognitive representations of the illness which
influence their actions regarding the threating situation .
According to the proponents of this theory,
individuals with living with chronic illnesses including diabetes
develop several perceptual components (e.g. perceptions
of illness identity, cause of illness, duration, consequence,
and curability or controllability) which influence how
patients interpret their illnesses. In applying this theory
to the study, we hypothesized that illness perception
could be negatively associated with the various
components of self-care practices of persons living with type-2
Design and sample
This study was based on a cross-sectional design which
allowed the researchers to collect data from a sample
within a particular a population at any one point in time.
This design was appropriate as this study was examining
relationships and predictive in nature [
]. All persons
living with T2DM and receiving health care at a public
health facility in Accra, Ghana constituted the
population for the study. This is one of the largest primary care
hospitals in Accra that provides care for diverse groups of
patients on daily basis. A total of one hundred and sixty
(160) participants were conveniently sampled for the
study. The participants were sampled and included in the
study if they met the following inclusion criteria: (1) aged
30 years and above; (2) have been living with diabetes for
a year or more; (3) willing to give informed consent or
assent to participate in the study.
Self‑care practices questionnaire [
This is an 11-item self-report questionnaire which
consists of five domains of diabetes self-care practices. These
domains include diet measured by four items (e.g. How
many of the last seven days have you followed a
healthful eating plan?), exercise measured by two items (e.g.
On how many of the last 7 days did you participate in at
least 30 min of physical activity), blood sugar testing
measured by two items (e.g. On how many of the last 7 days
did you test your blood sugar?), foot care measured by two
items (e.g. On how many of the last seven days did you
check your feet?) and the final subscale which is
medications was measured by one item (on how many of the last
7 days, did you take your recommended diabetes
medication?). These subscales were measured on a seven-point
Likert response format raging between 0 and 7. The mean
scores on the items were computed for the first four scales
to obtain the subscale scores each domain. The sum of the
subscales creates a composite score for total self-care. An
overall internal consistency value (α) of .76 was obtained
for this study.
Diabetes knowledge test 
This is a 24-item test which measures diabetes
knowledge among respondents. Each question has a correct
response and two wrong responses (True, False and
Don’t Know). One mark was awarded for each correct
response and the total possible score for each respondent
ranged between 0 and 24 with higher scores reflecting
higher diabetes knowledge. Some of the items on the test
include; “Eating too much sugar and other sweet foods is
a cause of diabetes”, “The usual cause of diabetes is lack
of effective insulin in the body”. A Cronbach alpha of .72
was found for the present the study.
Brief illness perception questionnaire 
This questionnaire has 9-items which measure patients’
cognitive and emotional representations of their
illness with regards to their perceptions of illness
consequences, duration, personal control, treatment
control, symptoms, coherence, concern, emotional
response, and causes. Examples of items on the scale
include; how much control do you feel you have over
your illness? The causal item was open ended to allow
respondents to indicate what they thought caused their
illness but was not used in this study. A total illness
belief or perception score was computed by adding the
responses on all the eight scales with possible scores
ranging between 0 and 80. A higher score indicates a
more threatening view about diabetes, that is, the
individual perceives the illness to be fatal and dangerous to
one’s survival. A Cronbach alpha of .78 was found for
the present the study.
Ethical clearance was obtained from the Greater Accra
Regional Health Directorate of the Ghana Health
Service. The clearance letter and the proposal for this
study were sent to the head of the La General
Hospital to seek permission to use the hospital as the study
site. After the head of the facility gave the permission
for the data collection, the patients receiving diabetes
care at the outpatients department of the diabetes unit
diagnosed with T2DM were approached. The objectives
of the study were explained to the patients and those
who agreed to participate in the study gave consent
or assent. The questionnaires were self-administered
or interviewer-administered depending on the level
of education of the participants. It took an average of
25 min for a questionnaire to be completed. The
completed questionnaires were retrieved from the
participants on the same day for coding and analysis. The
entire data collection was between January and
February, 2015. No incentive was provided as participation in
the study was voluntary.
All the ethical guidelines concerning the use of human
participants in research (e.g. informed consent,
confidentiality, privacy, no harm, voluntary participation etc.)
were strictly adhered to in the research process. Ethical
clearance was obtained from the Greater Accra Regional
Health Directorate of the Ghana Health Service which
is responsible for healthcare administration within the
Greater Accra region of Ghana.
Data was analyzed using the Statistical Package for the
Social Sciences version 21.0 for Window (IBM SPSS). To
determine the best predictors of self-care practices, two
analyses were conducted. First, the Pearson-moment
correlation coefficient (r) was conducted to examine
the relationship between the self-care practice and its
domains (diet, exercise, BST, foot care and medications),
illness perception and diabetes knowledge. Secondly,
regression fitted models were run using total self-care
and five domains as outcome variables. Only predictors
that had significant correlation coefficients with the
outcome variables entered into the regression models. We
thus conducted simple regression models where only
one variable was associated with any of the outcome
variables and multiple regressions when two or more
variables were associated with outcomes variables. All test
conducted were two-tailed and held statistical
significance at p < .05.
Demographic characteristics of the sample
The demographic characteristics of the sample are
presented in Table 1. Males comprised approximately 72%
of the sample, and approximately 92% of the participants
were over 40 years old (Mean = 60.3 years; SD = 12.04).
Only 5% of the participants were single, with 39.4%
currently married and 28.7% widowed. The majority of the
participants had junior secondary education (36.3%) and
high secondary education (23.1%), and about over a third
of the participants (33.8%) have lived with diabetes for
a period of 1–5 years. One average participant has had
diabetes for approximately 10 years. The majority of the
participants were Christians (87.5%) with the remaining
12.5% representing Islam, African Traditional Religion
(ATR) and other religions.
Relationship between diabetes self‑care practices and other study variables
The Pearson correlation analysis was performed to
examine the relationship between diabetes self-care practices,
illness perception and diabetes knowledge. The results
from the analysis as Table 2 showed that there is a
significant negative relationship between diabetes self-care
practices and illness perception (r = −.41, p < . 001). It
was also observed that a statistically significant
positive relationship exists between diabetes self-care
practices and diabetes knowledge (r = .31, p < .001). These
results suggest that when patients perceived their illness
to be threatening, they engage in less self-care practices
but when patients have higher diabetes knowledge, they
engage in more diabetes self-care practices.
The results as presented in Table 2 further showed that
patient’ dietary practices were significantly and negatively
correlated with illness perception (r = −.33, p < .001) but
positively correlated with diabetes knowledge (r = .46,
p < .001). Results also showed that exercise was
significantly and negatively correlated with illness perception,
(r = −.57, p < .001). However, patients’ diabetes
knowledge was significantly and positively correlated with
both blood sugar testing (BST) (r = .43, p < .001 and
foot-care (r = .18, p < .05). Adherence to medication was
not associated with both illness perception and diabetes
Predictors of diabetes self‑care practices
To determine the predictive effect of the illness
perception and diabetes knowledge on patients overall self-care
practices and domains of self-care practices, single and
multiple regression analyses were conducted. The results
presented in Table 3 showed that in the first model,
illness perception and diabetes knowledge jointly predicted
overall diabetes self-care practices, (R2 = .26, F = 27.05,
p < .001), explaining 26% of variance in the overall
diabetes self-care practices.
An examination of the subscales from the Table 3
showed that the model 2 significantly predicted diet
(R2 = .32, F = 37.26, p < .001). This means that illness
perception and diabetes knowledge jointly explained
32% of variance in dietary practices of T2DM patients in
the study. Further, the result from the model 3 showed
that only illness perception significantly predicted
exercise among T2DM patients explaining 34% of variance
in exercise behavior (R2 = .34, F = 39.83, p < .001). The
fourth model revealed that blood sugar testing was
significantly predicted by only diabetes knowledge explaining
B unstandardized coefficient beta, SE B standard error of B, β standardized coefficients beta
* p < .05
** p < .01
*** p < .001
19% of variance in their blood sugar testing (R2 = .19,
F = 18.12, p < .001). The fifth model showed that
footcare was significantly predicted by diabetes knowledge
explaining only 4% of variance in foot-care practices
among T2DM patients (R2 = .04, F = 3.03, p < .05).
This study sought to investigate whether illness
perception and diabetes knowledge of persons living with type-2
diabetes have any significant on their overall self-care
practices and domain specific practices. Self-care
practices among persons living with type-2 diabetes have been
associated with better diabetes outcomes and as such,
identification of variables that significantly predict these
self-care practices is very paramount within our Ghanaian
context. Results from the analysis showed that illness
perception significantly predicted overall self-care practices
among persons living with type-2 diabetes. That is, when
patients hold more threatening views about their illness,
they tend to engage in less diabetes self-care practices.
This could be due to that when patients view their illness
to be more threatening, they may adopt a fatalistic view
and thus, do not place much value on their own personal
recovery in the management of their illness.
This finding is consistent with previous findings that
showed that diabetes perception significantly influenced
self-care practices among persons living with type-2
]. The predictive effect of illness perception on
diabetes outcomes have also been documented within
the Ghanaian context with evidence suggesting that
illness perception significantly predict the levels of general
psychological distress, depression and anxiety levels of
persons living with diabetes [
]. The impact of illness
perception is not limited to the overall illness perceptions
as other researchers have found specific domains such as
timeline, controllability, severity and illness coherence to
predictive of diabetes self-care practices among a sample
of diabetic patients in developed countries [
Further analysis of the predictive effects of illness
perception on the domain specific diabetes self-care
practices showed that illness perception only predicted
diet and exercise practices among persons living with
type-2 diabetes which is partially consistent with earlier
findings by Broadbent et al. [
] that patients’ diabetes
perceptions influence their adherence to medication, diet
and exercise significantly. The findings from the current
findings have implications for the involvement of
psychologists in the delivery of diabetes care as the
cognitive and emotional representation of the illness by the
patients could pose a great challenge to their engagement
in diabetes self-care practices especially within the
dietary and exercise domains.
The effect of diabetes knowledge on the overall
selfcare practices and domain specific diabetes self-care
practices were also examined and the results from the
analysis showed that diabetes knowledge significantly
and positively predicted overall diabetes self-care
practices. This shows that the more knowledge diabetic
patients have about their illness, the more likely they
are to engage in diabetes self-care practices. This
finding is consistent with previous results that found diabetes
knowledge to be predictive of diabetes self-care
practices and diabetes management [
15, 16, 19
]. The findings
regarding the predictive effects of diabetes knowledge on
the domain specific diabetes self-care practices showed
that diabetes knowledge significantly and positively
predicted diet, blood sugar testing and foot-care
practices. These findings could be attributed to the fact that
engagement in these domain specific diabetes self-care
practices requires deep knowledge about diabetes and
the relevance of these specific practices to the
management process unlike medication that is widely known
to influence illness outcome. The outcomes are
consistent with the previous works by van der Heide et al. [
which found diabetes knowledge to be significantly
associated with domain specific diabetes self-care practices.
The findings from this study have some practical
implications for diabetes healthcare delivery. Firstly, the
significant associations found between the predictor variables
(illness perception and diabetes knowledge) and
diabetes self-care practices suggests that there is the need to
train healthcare providers (nurses) to address the chronic
care needs of persons with diabetes. Secondly, nurses and
doctors should be equipped with resources to address
the self-care needs of patients with diabetes in the form
of information leaflets and other relevant materials to
aid independent self-care. Such self-care information
should include information on causes, prognosis and
management strategies. Finally, since group education
is generally practiced at the various diabetes units, it is
recommended that individual needs should also be taken
into consideration due to variations in educational levels
and interpretation of the educational materials.
The findings of this study should be interpreted
cautiously in the light of some limitations. The use of a
cross-sectional survey design does not allow for the
generalization of the findings beyond the sample from
which data was gathered. The study did not also
consider impacts of personal demographic characteristics on
adherence to diabetes self-care practices neither was the
perceived causes of the illness measured. It is also worth
noting that the relationships examined do not reflect
diabetes control since no blood samples were analyzed for
HbgA1c or other physiological measures. Finally, the
collected data was based on self-report, and may
therefore, not be consistent with complications from a
medical point of view. However, it has been argued that that
perceived health and illness are often considered to be
more predictive of health behaviours and outcomes than
objective, medical indicators [
]. Despite these
limitations, this study has provided the foundation for future
empirical studies among persons living with diabetes in
relation to their diabetes management. Future study may
use qualitative design to understand the key motivations
to engage in diabetes self-care practices in terms of
barriers and facilitators.
The findings from this current study suggest that diabetes
self-care practices of persons living with type-2 diabetes
in Ghana are significantly influenced by their illness
perception and their level of diabetes knowledge. Therefore,
measures should be put in place to increase patients’ level
of knowledge and also, healthcare practitioners should
understand that how patients interpret their illness is
very significant in determining whether they will follow
the recommended self-care practices or not. The findings
from this study add to the existing scanty literature on
diabetes self-care practices within the Ghanaian context
as this study provides evidence that could be culturally
relevant to persons living with type-2 diabetes in Ghana.
BST: blood sugar testing; SD: standard deviation; SPSS: Statistical Package for
the Social Sciences; T2DM: type-2 diabetes mellitus.
NK, KOA and KA conceived and designed the study. KA collected the data and
data analysis was performed by NK and KOA. NK drafted the manuscript and
KOA revised the manuscript for quality, consistency and accuracy. All authors
read and approved the final manuscript.
We would like to thank the authorities and staffs of the La General Hospital in
Accra, Ghana for the permission to use their institution for the research. We
would also like to extend our appreciations to the participants for voluntarily
providing us with the needed information.
The authors declare that they have no competing interests.
Availability of data and materials
The data supporting our findings can be made available on request from the
Consent for publication
Ethics approval and consent to participate
Ethical clearance was obtained from the Greater Accra Regional Health
Directorate of the Ghana Health Service which is responsible for healthcare
administration within the Greater Accra region of Ghana. Written informed
consent was sought from all the participants in the study.
The authors have not received any financial assistance for this study.
Springer Nature remains neutral with regard to jurisdictional claims in
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