Identification of aspects of functioning, disability and health relevant to patients experiencing vertigo: a qualitative study using the international classification of functioning, disability and health
© Mueller et al.; licensee BioMed Central Ltd. 2012
Received: 23 December 2011
Accepted: 27 June 2012
Published: 27 June 2012
Aims of this study were to identify aspects of functioning and health relevant to patients with vertigo expressed by ICF categories and to explore the potential of the ICF to describe the patient perspective in vertigo.
We conducted a series of qualitative semi-structured face-to-face interviews using a descriptive approach. Data was analyzed using the meaning condensation procedure and then linked to categories of the International Classification of Functioning, Disability and Health (ICF).
From May to July 2010 12 interviews were carried out until saturation was reached. Four hundred and seventy-one single concepts were extracted which were linked to 142 different ICF categories. 40 of those belonged to the component body functions, 62 to the component activity and participation, and 40 to the component environmental factors. Besides the most prominent aspect “dizziness” most participants reported problems within “Emotional functions (b152), problems related to mobility and carrying out the daily routine. Almost all participants reported “Immediate family (e310)” as a relevant modifying environmental factor.
From the patients’ perspective, vertigo has impact on multifaceted aspects of functioning and disability, mainly body functions and activities and participation. Modifying contextual factors have to be taken into account to cover the complex interaction between the health condition of vertigo on the individuals’ daily life. The results of this study will contribute to developing standards for the measurement of functioning, disability and health relevant for patients suffering from vertigo.
KeywordsVertigo (MeSH) Outcome assessment (Health Care) (MeSH) Qualitative research (MeSH) Classification (MeSH)
Vertigo and dizziness are among the most common health problems in medical practice [1–5]. Vertigo and dizziness include both consequences of disease as well as definable disease entities such as benign paroxysmal positional vertigo, Meniere’s disease, or vestibular migraine. Irrespective of the various causes and underlying health conditions, vertigo and dizziness have significant impact on functioning and overall quality of life of the affected individuals To give some examples, the most common peripheral-vestibular disorder benign paroxysmal positioning vertigo – which is also the most frequent type of vestibular disorder – causes brief rotatory vertigo attacks, mainly triggered by rapid head movements, e.g. when turning around in the bed or lacing shoes. Central-peripheral disorders, which may be caused by brain ischemia, multiple sclerosis, or other permanent or transient brain lesions, can make vertigo attacks lasting from minutes to even weeks . In addition, vertigo and dizziness are a considerable burden to economy and health care [4, 7, 8].
Precondition of effective management and treatment of potentially disabling conditions like vertigo is – besides careful diagnosis of the underlying condition –the assessment of outcomes which are relevant to the patient. This is not only important to monitor treatment effects but also to set goals and to plan therapy .
As summarized by Morris et al.  outcome measures in vertigo vary by the entities they are addressing,, such as subjective experience of disability or signs and symptoms. Most of them reflect either the patients’ or health professionals’ experience. As an example, the frequently used Dizziness Handicap Inventory  addresses the patients’ experience of the consequences of vertigo on daily living.
Most outcome measures are developed and validated on the basis of empirical findings or professional experience . However, none of them refer to a common theoretical framework. A theoretical framework is fundamental for defining an outcome measurement and helps to ensure that the whole potential spectrum of issues is reflected .
In addition to the lack of theoretical foundation there is still no agreement on standards used to measure outcomes in patients with vertigo. This is illustrated by a recently published Cochrane Review in the field of vestibular rehabilitation which noted 15 different outcome measures of patients’ complaints in 21 studies .
The development of this international standard is based on the protocol to develop ICF Core Sets [16–18] and will therefore incorporate the perspectives of affected individuals, of health professionals, of current research as well as the epidemiological perspective.
to identify aspects of functioning and health relevant to patients with vertigo expressed by ICF categories and
to explore the potential of the ICF to describe the patient perspective in vertigo.
When did vertigo/dizziness occur the first time? How many years ago?
If you think about the functions of your body, your mind and your soul, what does not work the way it is supposed to?
If you think about your body, in which parts are your problems?
Activities and Participation
If you think about your daily life, what are your problems? If you compare your life before the occurrence of vertigo/dizziness with your life now, what has changed?
If you think about your environment and your living conditions, what do you find helpful or supportive? If you think about your environment and your living conditions, what barriers do you experience?”
If you think about yourself, what is crucial when handling your current situation?
Additionally collected data
To describe the study sample, sociodemographic and disease specific data (age, sex, living situation, medical diagnosis) was collected. Vertigo was categorized as either central-vestibular vertigo, peripheral-vestibular vertigo, somatoform vertigo or combination of types. To describe an overall impression on participants’ health, they were asked to appraise their health on a 5-point-Likert scale ranging from one to five were one indicates best health. In addition, the impact of vertigo on health was appraised by the Dizziness Handicap Inventory (DHI)  and the Vertigo Symptoms Scale (VSS). The DHI addresses self-perceived handicap due to vestibular disorders. The score ranges from 0 to 100, with a higher score indicating greater handicap. The VSS addresses frequency and severity of dizziness symptoms within the last 12 months. The score ranges from 0 to 4, with a higher score indicating more frequent and more severe symptoms.
Patients were recruited at the outpatient dizziness clinic at the Integrated Center for Research and Treatment of Vertigo, Balance and Ocular Motor Disorders (IFBLMU) at the Ludwig-Maximilians-Universität in Munich. Potential participants were contacted and asked for their willingness to contribute to a study by their physician in charge. In case of preliminary consent, the patients were provided with detailed information about the study. Informed written consent had to be signed prior to the beginning of the interview.
Inclusion criteria were over 18 years of age and adequate command of the German language. Positive vote of the ethics committee of the Medical Faculty of Ludwig-Maximilians-Universität in Munich was obtained prior to start.
The interviews took place subsequent to the consultation in the outpatient clinic in rooms of the hospitals. The interview was taken by an experienced registered nurse and bachelor student (EB) who was especially trained and ongoing supervised by the senior researchers (EG & MM). The interviewer was not part of the health care team.
The sample size was determined by saturation. Saturation refers to the point at which an investigator has obtained sufficient information from the field . In this study we defined saturation as the point during data collection and analysis when an interview revealed less than 5% additional ICF categories. The sampling strategy adopted the idea of theoretical sampling from the grounded theory methodology . In the selection process the researchers tried to balance relevant characteristics of the patients, such as gender, age and disease, to assure maximum sensitivity and to ensure a maximum of variety of experiences from the participants with different types of vestibular disorders to address those comprehensively.
Qualitative data analysis
The meaning condensation procedure  was used for the analysis of data content. In the first step, the interview transcripts were read through to get an overview of incorporated meaningful concepts. In the second step, the text was divided into meaning units, and the dominating theme for this unit was determined. A meaning unit was defined as a specific unit of text either a few words or a few sentences with a common theme. In the third step, the specific concepts contained in the meaning units were identified. For quality assurance reasons, the qualitative data analysis was conducted independently by two researchers trained in the methodology (MM, ES). The results were compared and discussed prior to further analysis.
Linking to the ICF
Scheme of qualitative data analysis and linking
,,I had to quit working in (…).“
Quitting gainful employment
d850 Remunerative employment
„I can’t drive my car anymore, even to the next town.”
Unable to drive cars
d4751 Driving motorized vehicles
Characteristics of the participants
age in yrs
Type of vertigo2
time with vertigo (in yrs.)
Vertigo Symptom Scale4
Dizziness Handicap Inventory5
ICF categories relevant in patients with vertigo (ICF component body functions)
Global mental functions
Temperament and personality functions
Maintenance of sleep
Specific mental function s
Appropriateness of emotion
Seeing and related functions
Hearing and vestibular functions
Vestibular function of balance
Sensations associated with hearing and vestibular function
Ringing in ears or tinnitus
Sensation of falling
Nausea associated with dizziness or vertigo
Pain in head and neck
Functions of the cardiovascular system
Increased blood pressure
Decreased blood pressure
Additional functions and sensations of the cardiovascular and respiratory systems
Exercise tolerance functions
General physical endurance
Sensations associated with cardiovascular and respiratory functions
Functions related to the digestive system
Regurgitation and vomiting
Weight maintenance functions
Sensations associated with the digestive system
Sensation of nausea
Control of voluntary movement functions
Coordination of voluntary movements
Gait pattern functions
Sensations related to muscles and movement functions
Functions of the skin
Other functions of the skin
ICF categories relevant in patients with vertigo (ICF component activities and participation)
Purposeful sensory experiences
General tasks and demands
Undertaking multiple tasks
Carrying out daily routine
Managing daily routine
Managing one's own activity level
Handling stress and other psychological demands
Changing and maintaining body position
Maintaining a body position
Maintaining a standing position
Carrying, moving and handling objects
Lifting and carrying objects
Fine hand use
Hand and arm use
Walking and moving
Walking short distances
Walking long distances
Walking on different surfaces
Moving around in different locations
Moving around within buildings other than home
Moving around outside the home and other buildings
Moving around using transportation
Using public motorized transportation
Driving human-powered transportation
Driving motorized vehicles
Mobility, other specified
Managing diet and fitness
Washing and drying clothes and garments
Cleaning living area
Caring for household objects and assisting others
Taking care of plants, indoors and outdoors
Taking care of animals
Particular interpersonal relationships
Relating with strangers
Relating with subordinates
Informal social relationships
Work and employment
Maintaining a job
Community, social and civic life
Recreation and leisure
Arts and culture
Recreation and leisure, other specified
ICF categories relevant in patients with vertigo (ICF component environmental factors)
Products and technology
Products or substances for personal consumption
Products and technology for personal use in daily living
Products and technology for personal indoor and outdoor mobility and transportation
General products and technology for personal indoor and outdoor mobility and transportation
Assistive products and technology for personal indoor and outdoor mobility and transportation
General products and technology for communication
Design, construction and building products and technology of buildings for private use
Natural environment and human-made changes to environment
Support and relationships
Acquaintances, peers, colleagues, neighbours and community members
Individual attitudes of immediate family members
Individual attitudes of friends
Individual attitudes of people in positions of authority
Individual attitudes of strangers
Individual attitudes of health professionals
Services, systems and policies
Architecture and construction services, systems and policies
Open space planning services
Transportation services, systems and policies
Health services, systems and policies
Labour and employment services, systems and policies
Labour and employment policies
Besides the most prominent aspect “dizziness” which was reported by all participants, most participants (9) reported problems within “Emotional functions (b152)” including appropriateness, regulation and range of emotions. Eight participants reported problems related to mobility (including walking and related functions and driving motorized vehicles) and carrying out the daily routine. In addition, almost all participants (11) reported “Immediate family (e310)” as a relevant modifying environmental factor. The next most frequent environmental factor was “Drugs (e1101)”, which was mentioned by seven participants. The results of the analysis of all interviews are shown in Tables 4, 5 and 6.
Our study indicates that patients with vertigo or dizziness consider many different aspects of functioning and health as relevant. Aspects from the component Activities and Participation were most prominently captured, followed by aspects covering Body Functions. Various environmental and personal factors contributed to the multifaceted picture of functioning in vertigo. In our study the ICF turned out to be a useful tool to code various impairments and restrictions caused by vertigo and dizziness and to describe disease specific functioning and quality of life since the majority of concepts in patients’ statements could be linked to the ICF.
Regarding the ICF component Body Functions participants reported, apart from obvious aspects (e.g. sensations associated with hearing and vestibular functions), orientation, temperament and personality functions, confidence, motivation, emotion, sleep, appetite and exercise tolerance as relevant. It is commonly recognized that vertigo has considerable impact on quality of life, but the distinct components are often unclear. Generic instruments such as the SF-36  give but a very general picture of impairment of mental functions. Anxiety and avoidance have been reported as psychological consequences of vertigo [1, 27]. Also, emotional problems seem to be associated with vertigo . Depression and somatization as well as increased obsessive-compulsive attitude have been observed .
" “(…) It really gets me down.” (b152 Emotional functions, Pt. 6)"
" „Okay, just from the beginning, I wanted to be left alone (…) I didn’t want to go anywhere (…) And when I got such panic attacks … nervous break down… because I don’t want to go outside (…). (b152 Emotional functions Pt. 009)"
" “And at night it is like…sleeping properly… does not work any more.” (b134 Sleeping functions, Pt. 001)"
Of the ICF component Activities and Participation, 62 categories were mentioned as relevant in our study. This underlines how much the pathology interferes with daily life. The reported categories ranged from very basic activities such as watching, listening and reading to more complex items such as managing daily routine, using transportation, self-care and housework:
" “When things pass by quickly… This is what you have to avoid and you actually do avoid… Just like watching TV. I haven’t been watching TV since December.” (d110 Watching, Pt. 001)"
" “I really loved reading. At the moment I can’t really read, because I get dizzy after a little while.” (d166 Reading, Pt. 009)"
" “When you want to go by bus, you have to take a rest at the bus stop…and then you have to get in the bus fast. And you have to get out fast and again… have a rest at the bus stop. Everything gets more complicated.” (d4702 Using public motorized transportation, Pt. 011)"
" “And I am happy to reach the toilet [without a vertigo attack]” (d530 Toiletting, Pt. 012)"
" “It’s worst when I have to do homework, for example when I have to hang curtains…” (d6402 Cleaning living areas, Pt. 008)"
It is obvious that all movements and body positions that are likely to provoke attacks were reported as restricted.
" „As soon as I was standing up… upright… [vertigo attacks occurred]… then walking was really hard (…).“ (d4104 Standing, Pt. 006)"
Almost all aspects of social participation were perceived as restricted, namely personal and formal relationships, employment, leisure, sports and community life. This is in line with the work of Neuhauser and colleges who showed in a large, community based study that up to 20% of individuals with vertigo avoid leaving the house . Dizziness is known to impede activities of daily life  and to interfere with workplace activities . Because attacks of vertigo are mostly uncontrollable and unpredictable, many patients suffer from the mere anticipation of the attack  which may be as restricting as the pathology itself .
" „Okay…but… now there is the vertigo (…) when I am standing in front of my customers, or employees… swaying… That doesn’t work!” (d730 Relating with strangers, d7401 Relating with subordinates, Pt. 009)"
" „[At work] I have to prepare these trolley tables all the time. Ist a permanent.. standing, bending, preparing… arround these trolleys… Then bringing them allover the building… four stories… I can’t imagine that I could handle this at the moment.” (d850 remunerative employment, Pt. 001)"
" “I would prefer going to work. But my ENT-doctor says that it’s too risky because of the spells… vomiting, high blood pressure, panic attacks,…” (d850 Remunerative employment, Pt. 001)"
Environmental Factors were reported as interfering and interacting with functioning. Among those were factors of the natural and built environment such as sounds, vibrations, climate, temperature, population density and architectural design. To give an example, paroxysmal positioning vertigo is suspected to be associated with temperature variation and air pollution .
" „Yes…, in daily life… crowdy places… where a lot of people… and noisy…This is what I cannot tolerate at the moment.” (e2500 Sound intensity, e2151 Population density, Pt. 001)"
" „And as I’ve said before, when I’m walking, strolling in the sun, I feel that the vertigo is even more extreme.” (e225 Climate, Pt. 008)"
Likewise, family, friends, neighbors, colleagues and their attitudes were reported as relevant environmental factors. They can act as facilitators or barriers for the individual affected by vertigo, since vertigo may change social roles and behaviors, also towards others .
" “I have two daughters. They give me a lot of support. And my husband.” (e310 Immediate family, Pt. 001)"
" „They, the people next to me, or acquaintances, too… When we went out for diner or to cinema… They knew that I suffer from vertigo attacks and that gave me the freedom… when I recognized: Oh! There is.... Then I could call them to help me: „Bring me to my car“(…).” (e420 Individual attitudes of friends, Pt. 012)"
In general, the ICF turned out to be a useful tool to describe the situation, determinants and consequences of vertigo. Only few concepts reported by the patients could not be coded with ICF categories. Most of them were related to personal factors, mostly coping strategies. As an example, some patients reported to visit only places which are save if a vertigo attack occurs, such as buildings that have staircases with handlebars, or places where they can lay down during a vertigo attack. Other patients reported to schedule trips or shopping more carefully. Coping strategies and resilience are reported in the literature as major determinants of symptom severity .
It was not the intention of our study to draw generalizing conclusions on experiences towards functioning and health of vertigo patients, or to report impact in various subgroups, or to compare them amongst others. We did include patients with different types of diagnoses in our study to ensure covering the widest range of experiences. The qualitative approach should always be the primary method to get a first idea about relevant aspects of functioning. As in quantitative studies, validity of this largely depends on the choice of participants. Participants should represent the typical range for which subsequent studies should be representative. The results of our study should provide a first selection of patient-relevant items which have to prove its validity in terms of frequency and discrimination before being implemented in further applications, such as future studies or clinical issues.
Some limitations have to be mentioned. On the one side, selection of patients for the interviews might be biased towards individuals with milder disease who are capable to undergo an interview procedure. On the other side, patients seen in a specialized tertiary care dizziness clinic may be selected towards those with more severe symptoms or more chronic conditions. However, our findings have high face validity and are in line with the studies conducted in this field.
Altogether, our study gives a first impression from the patients' perspective using the ICF regardless of potential selection bias.
From the patients’ perspective, vertigo has impact on multifaceted aspects of functioning and disability, mainly body functions and activities and participation. Modifying contextual factors have to be taken into account to cover the complex interaction between the health condition of vertigo on the individuals’ daily life. While there are generic and disease-specific instruments to measure Quality of life which do encompass several of the aspects found in our study, the ICF offers a broader perspective and a full understanding of all the factors involved at individual and health care level. The ICF has, therefore, a great potential to comprehensively describe functioning in vertigo for the assessment of burden of disease and treatment success. The results of this study will contribute to developing standards for the measurement of functioning, disability and health relevant for patients suffering from vertigo.
International classification of functioning disability and health
World health organization
Short form (SF)-36 health survey
Integrated center for research and treatment of vertigo balance and ocular motor Disorders
Dizziness handicap inventory
Vertigo symptoms scale.
We would like to express our gratitude to the participants for sharing their experiences in spite of the challenge of illness. We also thank the team of the outpatient dizziness clinic of the IFBLMU for recruiting the patients and support during field work. This project was supported by funds from the German Federal Ministry of Education and Research under the Grant code 01 EO 0901. The authors bear full responsibility for the content of this publication.
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