Running head: A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
A Critique of the Theory of Unpleasant Symptoms
Bridget Apple, Cathy Bozek, Jessica McClusky, & Christina Suwyn
Ferris State University
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A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
Abstract
The purpose of this paper is to examine the Theory of Unpleasant Symptoms (TOUS) by
Elizabeth Lenz and Linda Pugh. Within the theory’s development, the initial symptoms
addressed were dyspnea and fatigue. Representation of single concepts in different clinical
populations identified similarities across phases and concepts. The development of TOUS has
produced two conceptual levels and incorporated these concepts within a middle range theory
plane. At the single concept level, fatigue and dyspnea are seen. The multiple concept level
includes the study of fatigue during childbearing and also during dyspnea. At the middle-range
theory level, the process of unpleasant symptoms is observed.
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A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
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A Critique of the Theory of Unpleasant Symptoms
The Theory of Unpleasant Symptoms (TOUS) was introduced in 1995 and has since been
used in multiple studies. Its revision in 1997 brought a more general and adaptable theory. The
TOUS is a credible middle-range theory that has been used numerous times in nursing research
and will continue to be used in the future. The purpose of this paper is to both critique and
provide deeper insight into the TOUS.
Origins and Unique Focus
Origins of the TOUS focus on the authors’ development of a description of fatigue and
dyspnea, and the beginning efforts to document regularities between these concepts. The
authors’ relationship first developed when Pugh and Milligan were studying fatigue at two
different perinatal phases and united their ideas (Pugh & Milligan, 1995). These ideas were
integrated to develop a model of fatigue during the birthing process. The second relationship
began when authors Gift and Pugh recognized that their concepts were similar and they
identified commonalities between the two symptoms of fatigue and dyspnea (Lenz et al., 1995).
After the second relationship was recognized, the work was at the multiple concept level, as it
could span more than a single symptom. The formation of a general model that could be
extended to multiple symptoms and different clinical populations was on the horizon.
In the theory, dyspnea is subjective, as it is only measurable by patient report (Lenz et al.,
1995). Lenz et al. (1995) also explains that dyspnea is described similarly to pain. This was
when the second development was formed, which linked dyspnea and pain together. During the
study of fatigue during childbearing, Milligan and Pugh combined their studies of fatigue from
the postpartum and intrapartum periods. Both studies showed a similarity of fatigue producing a
“snowball” effect (Lenz et al., 1995, p. 8). Gift and Pugh began to see connections between the
A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
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concepts of dyspnea and fatigue. Both symptoms are defined as subjective, acute or chronic,
occur during abnormal or normal conditions, and can be exacerbated by or the result of anxiety
or depression (Lenz et al., 1995). Consequently, dyspnea and fatigue can affect activities of
daily living and social well-being. Here, the basis of the TOUS was created when the studies of
fatigue during childbearing and dyspnea and fatigue were combined (Lenz et al., 1995).
Clarity and Simplicity
While a theory’ utilization may have great potential in the care of individuals, it is useless
if it cannot be understood and applied. Theory needs to be constructed in a manner that is easily
understood and where its utilization planning can be readily accomplished. Thus, the
comprehensiveness of a theory is validated based on whether the theory clearly states the main
contents and whether it is easily understood by the readers while avoiding oversimplification
(Fawcett, 2005). TOUS accomplishes this task by providing clarity and simplicity in its
formation.
Clarity is defined as transparency within perception or understanding with “freedom from
indistinctness or ambiguity” (Clarity, 2009). The TOUS provides clarity through its consistency
of defined concepts and presented explanations. The theory uses the study of dyspnea and
fatigue, allowing pain to be an analog, to combine the descriptions of both findings, resulting in a
common understanding (Lenz & Pugh, 2003).
Barnum suggests that internal and external criticisms need to be defined by theories and
that clarity should be located within the theory (Dudley-Brown, 1997). The internal criticisms
are composed of “clarity, consistency, adequacy, logical development, and level of theory
development” (Dudley-Brown, 1997, p.78). Meleis states that the clarity of a theory is found in
the relationship between the structure and function that have a clear and logical progression of
A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
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development (Dudley-Brown, 1997). The TOUS illustrates this logical progression through the
researchers’ initial discovery where that their unrelated focus’ of dyspnea and fatigue shared
some of the same characteristics. From there, the researchers began to compare study findings
and to develop further research to aid in the development of the TOUS. This clear progression of
inquiry, research, development, additional research, and then modification based on critics of
their peers, validates the clarity of the TOUS.
Fawcett, (2005) includes parsimony as a needed criterion for a workable theory.
Parsimony is defined as simplicity or frugality with words or actions (Parsimony, 2012). While
the written descriptions of the TOUS are evident throughout its format, the authors aided to the
simplicity of the theory through working illustrations to show the interactions and flow of the
theory.
The major concepts of symptoms and performance outcomes, along with the interrelated
categories of psychological, physiological, and situational factors provide a framework for the
metaparadigms of the TOUS (Lenz & Pugh, 2003). The original version of the TOUS theory
provided an illustrated framework which simplified and provided an organization of ideas and
concepts (see Figure 1). After revision, the authors of the TOUS supplied an updated version of
the TOUS diagram (see Figure 2). While the increased intricacy of the diagram is not to be
disputed, it continues to foster a clear and concise understanding of the TOUS while illustrating
the multi-dimensional aspects of the theory, and the overlapping domino affects that the
symptoms, factors and performance outcomes experience. Therefore, it is not only through the
structure of the TOUS, but also through the visual reinforcement provided by the diagrams that
this theory demonstrates simplicity.
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Figure 1. Original illustration of the TOUS. Adapted from “The middle-range theory of
unpleasant symptoms: An update,” by Lenz, E. R., Pugh, L. C., Milligan, R. A., Gift, A., &
Suppe, F., 1997, Advances in Nursing Science, 19(3), 14-27. Retrieved from
http://www.ncbi.nlm.nih.gov/pubmed/9055027
Figure 2. The updated TOUS. Adapted from “The middle-range theory of unpleasant
symptoms: An update,” by Lenz, E. R., Pugh, L. C., Milligan, R. A., Gift, A., & Suppe, F., 1997,
Advances in Nursing Science, 19(3), 14-27. Retrieved from
http://www.ncbi.nlm.nih.gov/pubmed/9055027
A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
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Theory Generation
The TOUS has great potential to generate further theories. The theory was developed
using information from prior models and continues to be built upon by researchers (Lenz et al.,
1997). When the TOUS was first introduced in 1995, “the authors acknowledged that further
development of the model and theory was needed to account for the opportunity of experiencing
more than one symptom at a time” (Myers, 2009, p. E3). In 1997, the theory was revised to
include this criteria and to further develop the ideas that the original TOUS contained.
Additionally, more theories could potentially be developed because the TOUS has been
verified by multiple different studies. According to Lenz et al. (1997), “several published studies
about other symptoms (eg, pain, nausea, and other gastrointestinal symptoms) have yielded
findings that are consistent with the theory” (p. 25). Time after time, the TOUS has been proven
accurate by studies, and also beneficial to researchers in various clinical areas.
Credibility
When TOUS began it was directed at two symptoms but has developed into a more
general theory. According to Myers (2009):
The theory evolved from collaboration among three individual investigators who began
work on two concepts that represent unpleasant symptoms. [...] The investigators noted
commonalities between the two concepts and subsequently realized that a more general
theoretical formulation would be appropriate for describing multiple symptoms [...]
across different clinical populations. (p. E3)
In addition, “middle-range theories are abstract, yet are at a level of concreteness that provides
linkages with research and practice” (Lenz et al., 1997, p. 14).
A CRITIQUE OF THE THEORY OF UNPLEASANT SYMPTOMS
The TOUS has been used by researchers in studies involving various types of diseases
and symptoms. Some of these studies include: “...Chemotherapy-Related Changes in Cognitive
Function” (Myers, 2009), “Symptom Clusters in Heart Failure” (Jurgens, 2009), and “Symptom
Burden in Inflammatory Bowel Disease” (Farrell & Savage, 2010). The fact that several
researchers have used the TOUS, and proven it to be useful, in their studies speaks volumes for
the theory.
Testability
The TOUS has been tested in various situations with different patients and symptoms as
the focus of the studies. Fawcett (2005) defines testability as being met when “specific
instruments or experimental protocols have been developed to observe the theory concepts and
statistical techniques are available to measure the assertions made by the proposition” (p. 133).
The TOUS exclusively uses patient reported data, divided into areas of symptoms, influencing
factors, and performance outcomes (Lenz & Pugh, 2003). Though this data is not observable, it
can still be considered testable. This was determined using the three suggested questions on
testability from Fawcett. First, the research has been shown to adequately reflect the basis and
purpose of the TOUS. Next, the data is collected through patient reports, which provide a
picture of the symptoms being experienced, despite not being an observable indicator. Finally,
the data collection can provide a measurement of the theory’s claims. For example, while the
researchers were unable to observe all of the symptoms of the patient, the data clearly shows
whether the patient experiences an improvement or decline in their perception of their health
after appropriate interventions were provided. A patient complaining of pain could also show
increased anxiety about a new diagnosis. After providing the patient with the suitable care to
decrease that anxiety, the researcher would be able to see if the patient reports an increase,
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decrease, or no change in that pain level. It is the change in the patient reported pain level that
would be the indicator of the success or failure of the theory. Consequently, the TOUS is
testable.
Contribution to Nursing
The TOUS was utilized by Tyler and Pugh (2009) to observe the relationship between the
theory and a bariatric surgery patient. Bariatric surgery patients are an ideal population with
which to test the TOUS, since they involve not only management of physical symptoms, but also
a steady support group in their home lives. In this study, it was found that the patient initially
reported many poor symptoms such as fatigue, vomiting, constipation, and abdominal pain
immediately following surgery. Upon further investigation, the researchers discovered that the
patient’s significant other was incarcerated shortly after her surgery, and her mother and sister
were not supportive of the procedure as a whole. This culminated in a loss of an environmental
support system and an increased amount of stress on the patient and her five children. Using the
TOUS, these environmental and psychological factors were identified, and could be successfully
addressed. Following the improvement in these two areas, the patient’s physiological symptoms
began to resolve (Tyler & Pugh, 2009).
In another example, Myers (2009) looked at the relationship between the TOUS and
chemotherapy-related changes in cognitive function. This study discussed the symptoms
commonly experienced during chemotherapy. Myers felt that the TOUS was successful in
describing both the occurrence of symptom clusters as well as the interrelationship between the
symptoms and their contributing or situational factors. For example, the author discusses the
benefit of the theory to aid in answering whether depression, anxiety, and fatigue contribute to a
decline in cognitive function, or vice versa.
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Both of these studies illustrate the value of the TOUS to nursing practice. By taking a
generic and multi-symptom view of the patient, the nurse is able to identify psychological or
situational factors that may contribute to the manifestation of certain physiological symptoms. In
this way, the TOUS is invaluable for nursing practice. Instead of treating all physiological
symptoms with additional medications, the nurse is able to develop a holistic plan that targets the
root cause of the symptom. In addition to being able to be used retroactively, the nurse is able to
use the theory proactively by putting mental health or support systems in place prior to a surgery
or hospital stay. An example of this is the use of support groups prior to bariatric surgery, as
suggested by Tyler & Pugh (2009). Using the TOUS to help prevent patients from experiencing
symptoms initiated or exacerbated by psychological or situational stimuli, nursing can focused
on holistic care, health promotion and disease prevention (Chiverton, Votava, & Tortoretti,
2003).
Conclusions
The TOUS has evolved from a specific theory to a much more general and applicable
one. As evidenced by the studies mentioned, the theory has been shown to be successful in
providing insight into symptoms in patients with a wide range of diagnoses. The TOUS is
presented in a way that is clear and credible, allowing for seamless use in the clinical realm.
Along with this clarity, the TOUS provides the nursing profession with methods that ease the
severity of symptoms through a holistic approach that benefits the patient on a physical,
emotional and mental level. In this way, the TOUS is invaluable to nursing practice.
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