Health literacy, pain intensity and pain perception in patients with chronic pain
Health literacy, pain intensity and pain perception in patients with chronic pain
Philipp Johannes Köppen 0 1 2 3 4
Thomas Ernst Dorner 0 1 2 3 4
Katharina Viktoria Stein 0 1 2 3 4
Judit Simon 0 1 2 3 4
Richard Crevenna 0 1 2 3 4
0 K. V. Stein International Foundation for Integrated Care , Oxford , UK
1 P. J. Köppen Landesklinikum Hochegg , Grimmenstein , Austria
2 P. J. Köppen · T. E. Dorner ( ) Centre for Public Health, Department of Social and Preventive Medicine, Medical University Vienna , Vienna , Austria
3 R. Crevenna Department for Physical Medicine, Rehabilitation and Occupational Medicine, Medical University of Vienna , Vienna , Austria
4 J. Simon Centre for Public Health, Department for Health Economics, Medical University Vienna , Vienna , Austria
Summary Background Chronic pain poses a large burden for the healthcare system and the individuals concerned. The impact of health literacy (HL) on health status and health outcomes is receiving more and more attention. The aim of this study was to evaluate the association of HL with chronic pain intensity and pain perception. Methods A total of 121 outpatients suffering from chronic pain (pain duration >3 months) were evaluated. The HL was measured using the health literacy screening questions. Pain intensity was measured with a Visual Analogue Scale (VAS) and pain perception with the short-form McGill Pain Questionnaire (SF-MPQ). Results Individuals with low HL had significantly higher VAS values (Pearson correlation coefficient = -0.270, p = 0.003). Stepwise regression analysis showed that HL has a significant association with pain intensity (odds ratio [OR] = 2.31; 95% confidence
Educational status; Pain management; Self-management; Patient participation
interval [CI] 1.11–4.83), even after controlling for age
and sex (OR = 2.27; 95% CI 1.07–4.82), but no longer
after controlling for education (OR = 2.10; 95% CI
Conclusion Individuals with a higher HL showed less
pain intensity, which seems to be caused by a better
pain management; therefore, supporting the
development of HL in patients with chronic pain could be
seen as an important objective of integrated care.
Chronic pain causes huge financial costs for the
society and imposes a significant emotional and physical
burden on the individuals concerned [
prevalence of chronic pain in Austria is 21%. The average
pain duration is 5.8 years, 31% of the persons
surveyed in Austria said that their pain is not adequately
controlled and only 16% had seen a pain management
specialist. In comparison, the prevalence of chronic
pain in Europe is 19% [
]. Chronic pain causes high
direct costs through therapies and high indirect costs
through reduced productivity of the patients [
Out-of-pocket costs for individuals with chronic pain
in Austria amount to 2349 a year and the persons
concerned have an extra expenditure of more than
5 h per week for consultations and therapies . The
persons concerned also have a reduced quality of life
Health literacy (HL) is defined “as the cognitive and
social skills which determine the motivation and
ability of individuals to gain access to, understand and
use information in ways which promote and maintain
good health” [
]. In the European health literacy
survey (HLS-EU), the biggest survey about HL in Europe
so far, 18.2% of the Austrian population had an
inadequate HL, 38.2% a problematic HL, 33.7% a sufficient
HL and 9.9% an excellent HL. Of the eight surveyed
countries, only Bulgaria and Spain had poorer results.
Predictors for low HL are financial deprivation, low
social status, low education and old age [
Low HL is associated with poorer health-related
knowledge and comprehension, increased
hospitalizations and emergency care and especially among
elderly persons as shown by poorer overall health status
and higher mortality [
]. According to Mackey et al.
], low HL influences the development of
self-management skills which are key resources for the
treatment of chronic diseases. There is only little
literature about the impact of low HL on chronic pain. In
a study from Devraj et al. it was found that in a group
of patients with chronic pain the persons with low HL
had poorer pain medication knowledge, did not know
where to find health care professionals to help them
manage their pain, and had very little knowledge of
non-medication modes of treating pain. No impact of
HL on pain intensity was found [
]. In an Australian
study from 2010, HL and beliefs about pain between
groups with and without chronic low back pain were
compared. There was no difference in HL as
measured with the Short Test of Functional Health
Literacy in Adults (S-TOHFLA) between the groups but in
a qualitative analysis of interviews, the group with low
back pain reported difficulties in seeking,
understanding and using medical information about chronic low
back pain [
]. Loke et al. [
] found no consistent
association between low HL and poorer functional
outcomes in their systematic review about patients with
chronic musculoskeletal diseases. The heterogeneity
of existing findings suggests a potential influence of
cultural and health care system contexts on the
relevant association between HL and pain management
skills. The current study aimed to assess whether there
is an association between HL on pain intensity and
pain perception in a heterogeneous group of patients
with chronic pain in Austria.
Outpatients suffering from chronic pain (with a pain
duration more than 3 months) were included, with the
goal to evaluate the association of HL with chronic
pain intensity and pain perception.
After piloting, data were collected in three
outpatient departments (Clinic for Physical Medicine and
Rehabilitation, Headache Outpatient Clinic of the
Department of Neurology, Pain Outpatient Department
of an Orthopedics Hospital) in Vienna between
December 2012 and February 2014. The survey took
place within the study “Chronic pain and its
development depending on social environment, health
literacy and previous treatment of the patients and the
costs incurred”. In the Clinic for Physical Medicine
and Rehabilitation, all patients who fulfilled the
inclusion requirements were informed about the survey
by the physicians after standard consultation. If they
agreed to participate and signed an informed
consent, they were interviewed face to face with a
predesigned questionnaire by a medical student as part
of the same appointment. From December 2012 to
May 2013 44 patients were interviewed in the Clinic
for Physical Medicine and Rehabilitation. The
feasibility of the same approach was questioned during
piloting between June and July 2013 in the Headache
Outpatient Clinic; therefore, here a different
recruitment protocol was implemented. All patients treated
from January 2012 till July 2013 in the clinic were
informed about the survey in a letter and contacted by
telephone afterwards and an appointment for the
interview was agreed with the persons interested. A
total of 22 patients of the Headache outpatient clinic
were interviewed. In the orthopedic hospital, a
total of 55 patients were recruited in the outpatient
department as well as in the ward between November
2013 and February 2014. The patients who fulfilled
the inclusion criteria were informed about the survey
by a medical student and interviewed face to face
after they signed an informed consent. The inclusion
criteria in all centres were:
● Chronic pain (at least 3 months duration)
● Age between 18 and 65 years
● Sufficient knowledge of the German language
● No current malignant disease
● No current inpatient treatment in a psychiatric ward
The HL was measured using three HL screening
questions from the publication “Brief Questions to Identify
Patients with Inadequate Health Literacy” [
three questions “how often do you have someone help
you read hospital materials”, “how confident are you
filling out medical forms by yourself” and “how often
do you have problems learning about your medical
condition because of difficulty understanding written
information?” were translated into German using the
method of retranslation. The answers on the 5-point
Likert scales were rated with 1 point for the worst
answer option and 5 points for the best answer option.
A total score was calculated, with 15 points as the
best possible value and 3 points as the worst possible
To assess the source where patients get their
information about pain from, the following question
was asked: “from where do you obtain information
about your pain disease?” Multiple answer options
were possible including: doctor/journal/TV/radio/
internet/informative lectures/self-help groups/family
Pain intensity was measured using a Visual
Analogue Scale (VAS) [
]. Pain perception was measured
using the short-form McGill Pain Questionnaire
(SFMPQ). Besides pain intensity, the SF-MPQ also records
sensory and affective components of pain. The
SFMPQ consists of three components. The main
ponent is made up of 11 sensory and 4 affective
descriptors. The descriptors are rated from 0 (none) to
3 (severe), this leads to a maximum score of 45 in this
component. The second component is the present
pain intensity index (0 to 5 points) and the third the
VAS. The total added score ranges from 0 to 60 points
]. No established critical cut-off points exist for
interpretation. A higher score means worse pain [
For this study, the German version of Oesch et al. [
was used. Pain duration was listed in months. Pain
localization was elicited with the question “on which
parts of the body does the pain occur?” To answer the
question, the participants were presented a
homunculus with 14 defined parts of the body, with
multiple answers possible. General sociodemographic data
collected included age, sex, country of birth, highest
level of education, monthly household income,
employment status and sick leave/in-patient care or
rehabilitation in the last 3 months.
A correlation analysis was performed for HL, pain
intensity, pain perception and pain duration. In order
to quantify the possible influence of the HL on the
pain parameters, three stepwise logistic regressions
were performed with the dependent variables pain
intensity (VAS), pain perception (SF-MPQ) and pain
duration. The independent variable was HL and
covariables sex, age and education. Because none of the
parameters HL (Kolmogorov-Smirnov 0.000), pain
intensity (Kolmogorov-Smirnov 0.001), pain perception
(Kolmogorov-Smirnov 0.000) and pain duration
(Kolmogorov-Smirnov 0.000) were normally distributed,
these four parameters were dichotomized by the
median. To investigate the influence of the co-variables
sex, age and education at HL a logistic regression with
HL as dependent variable was performed. All
statistical analysis were performed using SPSS Statistics 19.
The study was approved by the Ethics Committee
of the Medical University of Vienna (No. 1624/2012)
A total of 121 participants completed the
questionnaire. For demographic data see Table 1. The HL score
had a median of 13, a maximum of 15 and a
minimum of 5. Table 2 shows the findings for the three HL
screening questions. It turned out that for each of the
three questions, over 60% of the participants chose the
two best answers. For two of the questions (“how
confident are you filling out medical forms by yourself?”
and “how often do you have problems learning about
your medical condition because of difficulty
understanding written information?”) more than 50% chose
the best possible answer. The descriptive statistics for
the different pain parameters are shown in Table 3.
The correlation analysis showed that higher
values of the HL score correlated borderline moderately
with lower values of the VAS (Pearson correlation
coefficient = –0.270, p = 0.003). Between the HL score
Pain duration, months (years)
Pain perception, SF-MPQb
and the SF-MPQ no correlation could be found
(Pearson correlation coefficient = –0.022, p = 0.814) and the
HL score and pain duration practically did not
correlate with each other either (Pearson correlation
coefficient = 0.083, p = 0.369).
A correlation analysis was performed for HL score
and the co-variables sex, age and education (Table 4).
It was found that there was no correlation between the
parameters and thus no multicollinearity between the
covariables and HL and among themselves.
The findings of the stepwise logistic regression
analysis showed a significant effect of HL on pain
intensity. The effect was still significant after
controlling for sex, as well as after controlling for sex and
age. After additional control for education the OR was
2.10, though the effect was not significant anymore.
In contrast to these findings, there was no significant
effect of HL on pain perception and on pain duration
Fig. 1 shows the sources of information as used by
the participants. For patients with chronic pain, the
general practitioner was the most frequently
mentioned source followed by the internet. Self-help
groups were mentioned least.
Lower HL was associated with higher rates of pain
intensity as measured on the VAS. There was no
correlation between HL and pain perception. No association
was found between HL and pain duration either.
Although the relationship between HL and pain
intensity is not clear so far, there are indications that pain
intensity is influenced by low knowledge about pain
management and poor coping strategies of persons
with lower HL [
]. Also, Van Hecke et al. 
found an association between higher pain intensity
and inadequate HL. It is also known that knowledge
translation (KT) can help to reduce the burden of
persistent pain [
]. Knowledge is a key component of
behavioral change and the success of chronic pain
treatment is affected by the motivation and ability of the
patients to implement these changes in daily life. The
KT interventions can lead to positive effects on patient
function in short-term and medium-term; however, it
is not clear whether other outcomes are also improved
by KT interventions [
]. When one considers that
patients report difficulties to understand their
physicians because of the complex medical jargon used
], it seems important to implement strategies to
enhance patient comprehension. These strategies
consist of jargon-free communication, the usage of
pictorial aids, the targeted communication of key points at
every consultation, and the usage of the “teach-back”
method to confirm patients’ understanding [
Another aspect that should receive attention is the fact
that it is most challenging to get access to qualitative
information for individuals with the lowest levels of
HL. Furthermore, for physicians it is most
challenging and time-consuming to enhance comprehension
and HL of persons with low basic skills in literacy and
Our findings on the large difference between the
influence of HL on pain intensity and pain perception
leads to the question of the measurement validity of
these two parameters and may help to choose which
one is more important to measure in patients with
Spearman-cc Spearman correlation coefficient
chronic pain. The main difference between the VAS
and the SF-MPQ is that the SF-MPQ measures,
besides the quantity of pain intensity, additionally the
quality (sensory and affective) of pain [
] suggested that these instruments measure
different aspects of pain. The results can be influenced by
the instructions given to the patients. A study with
patients after radical prostatectomy showed that the
group of older men had lower scores on the MPQ than
the younger group while there were no differences on
the VAS [
]. According to Coll et al. [
] the SF-MPQ
is more appropriate to measure pain intensity than
pain duration and pattern over time. Since all these
findings result from research about postoperative pain
and not about chronic pain it stays unclear why there
were such big differences between the VAS and the
SF-MPQ, taking into account that the VAS is integral
part of the SF-MPQ. But there is evidence that pain
intensity can differ significantly between different pain
Limitations in the measurement of pain in chronic
pain patients are a confusion about the definition of
pain, a difficulty of averaging pain and the fact that
pain measurement is influenced by things other than
pain. The confusion about the definition is relevant
especially for patients with neuropathic pain who are
uncertain whether paresthesia and uncomfortable
numbness should also be referred to as pain.
Secondly, the difficulty of averaging pain is important
for chronic pain, because the pain level often varies
considerably between different days and also during
a single day. Thus, it is difficult to appoint the
intensity of the pain with a single value. Thirdly, patients
often incorporate dimensions of pain (e. g., affect,
interference) and constructs outside of the pain
experience (e. g., what the interviewer might think) into
their pain intensity ranking [
In our findings the level of education had a
significant influence on the level of HL. After control for
education, the influence of HL on pain intensity was not
significant anymore<, therefore, the level of education
affects the pain intensity of the patients. These
findings are in line with the findings of other authors [
]. Well-educated persons have a better
self-management of pain therapy and better coping-strategies.
Van der Heide et al.  found that HL has the role
of a mediator in the relationship between education
There was no correlation between HL and pain
duration. The fact that HL has an effect on pain
intensity but not on pain duration can be explained
through the continuous development of HL in
people with chronic conditions. The development of HL
is strongly influenced by the healthcare professionals
the patients consult with their pain. Patients can be
encouraged by their doctors to engage with
informaFig. 1 Prevalence of the
usage of sources to
information with multiple answers
tion about their disease and actively take part in
decisions about their therapies. Other factors that help
increase HL are a high personal motivation and fear
of negative consequences of the disease or operations.
Factors that inhibit the development of HL are lack of
personal motivation, non-acceptance of the
diagnosis and passing the responsibility onto the physicians
To assess the relationship between HL and chronic
pain it is also important to look at the sources from
where the patients got their information. The
frequency distribution for the question “from where do
you obtain information about your pain?” showed
that the majority of patients have confidence in their
doctors when it comes to where to get information
about their disease: but it is important how much
of the given information is understood and
remembered by the patients. Many patients have problems
to understand the instructions from their physicians
]. Most common mistakes made by physicians
are the use of medical jargon, delivering too much
information at one encounter, and to miss confirming
patients’ understanding. In medical educations for
students as well as for practitioners, HL and strategies
of clear patient communication should be
]. In their Health Literacy Conference
Report 2008 the European Patients Forum (EPF) [
recommended development of a guideline to help
health care professionals providing user-friendly
information for the average citizen. Particularly suitable
to enhance patients’ understanding is the
combination of visual with written or oral information [
The internet has an increased importance as a
source of health information in our study in
comparison to earlier studies [
]. This finding could
be expected, because the use of the internet in the
population of industrial countries increased rapidly
in the last years, in Germany from 37.0% in 2001 to
76.8% in 2014, for example . Individuals with
a high education status use the internet more often
as a source than those with a low education status
]. Less than half of chronic pain patients who use
the internet for pain-related information discuss their
own findings with their physicians [
]. This may be
because the quality of the information found on the
internet is often unclear and patients may not
understand it enough to actively use the information. Only
3.3% of the participants received their pain-related
information from self-help groups. This may indicate
that chronic pain patients hardly use self-help groups
and there is only little knowledge transfer between
individuals concerned with chronic pain. According
to Dierks et al. [
], self-help groups play an
important role for individuals with chronic conditions. The
progressive establishment of self-help groups can be
seen as a reaction to a deficiency to provide
information by the healthcare system. Evidence about the
utilization of self-help groups generally and in
particular for chronic pain patients is rare [
]. This field
needs to be investigated profoundly considering that
group medical visits can help patients to reduce pain
through pain education, improved self-management,
and the exchange with other chronic pain patients
Limiting factors on validity of the study are the
inclusion criteria “Age between 18 and 65 years” and
“sufficient knowledge of the German language”. Thus,
two high risk groups for low HL, older people and
persons with poor ability to speak and read German,
were excluded from the study. The measured HL in
the study population might be higher than in a
population without these exclusion criteria. This
distortion could be reinforced by the self-selection bias of
the recruitment. The health literacy screening
questions were translated into German using the method
of retranslation; however, it is not a validated
instrument to measure HL in a German speaking
population. Another bias could result from the fact that the
interviews were performed by different persons in
ferent places under different circumstances.
Furthermore, self-reported measures of HL could be biased
by the influence of shame of the participants [
Our findings confirm the mediator effect of HL for
pain intensity but not for pain perception and pain
duration. A higher HL could empower chronic pain
patients for better self-management and more
adequate coping strategies when exposed to pain. As
HL is a competence that develops continuously, it
is important to support this development during the
therapy. This, of course, is a challenge for the
attending physicians. The provided information should
be prepared and communicated individually,
according to personal needs and knowledge.
Comprehension of the provided information should be ensured
through the teach-back method and not be taken
as a self-evident fact. Furthermore, patients
searching for information should be actively supported by
their physicians. Future research should investigate
the personal attitude and competences of physicians
about knowledge transfer with an individual approach
and also including community-based initiatives and
mass media campaigns and HL [
aspect that should receive attention is the difference
between the pain intensity measured by different
instruments. Furthermore, the role and potential of
self-help groups to help relieve the burden of chronic
pain in Austria should be investigated.
Funding Open access funding provided by Medical
University of Vienna.
Compliance with ethical guidelines
Conflict of interest P.J. Köppen, T.E. Dorner, K.V. Stein, J.
Simon and R. Crevenna declare that they have no competing
Ethical standards All patients who participated in the study
signed an informed consent.
Open Access This article is distributed under the terms of
the Creative Commons Attribution 4.0 International License
permits unrestricted use, distribution, and reproduction in any
medium, provided you give appropriate credit to the
original author(s) and the source, provide a link to the Creative
Commons license, and indicate if changes were made.
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