Transcript Chapter 15: Treatment Outcomes Across the Disablement Spectrum

Chapter 15
Treatment Outcomes Across the
Disablement Spectrum
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
Chapter Overview
• Performing research on injured or ill patients is
important to advancing the health sciences.
• The importance of selecting appropriate outcomes
measures to assess in patients as their pathology
progresses over time.
• Conceptual framework for the measurement of
treatment outcomes.
• Delineate between disease-oriented and patientoriented measures.
• Global and region-specific measures.
• How to choose the appropriate outcomes instruments.
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Types of Outcomes Measures
Outcomes Measures in the Health Sciences
 Disease-oriented evidence (DOE): measures that provide
insight into the physiology of illness or injury
 Provides information of most interest to health care providers,
rather than patients
 Examples: blood pressure, electromyographic activity
 Patient-oriented evidence (POE): information that is
subjectively self-reported by patients as opposed to gained
from objective clinical or laboratory measures.
 Consists of measures that are of direct interest to patients, rather
than clinicians
 Examples: severity of symptoms, level of function, and quality of
life; also financial outcomes such as cost of health care services
 POE is sometimes referred to as patient-oriented
evidence that matters (POEM).
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Disablement Models
• The measurement of treatment outcomes in clinical
research must be built upon disablement models.
• Disablement models put forth by organizations:
–
–
–
Institute of Medicine
World Health Organization
National Center for Medical Rehabilitation Research
• A common foundation for all of these models is the
emphasis on the psychosocial functioning of the individual
patient (POE) as opposed to the physiological functioning of
the patient (DOE).
• Saad Nagi (1960’s): the concept of disability as a
sociological construct.
• Disability: the inability or limitation in performing socially
defined roles and tasks expected of an individual within a
sociocultural and physical environment. This definition is in
contrast to the common perception of disability as a
permanent physical or mental handicap.
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Examples of Four Patients Using Nagi’s
Disablement Model
Patient
Demographics
Active Pathology
20-year-old female collegiate
basketball player
35-year-old male roofer
35-year-old female lawyer
Knee ligament sprain
Knee ligament sprain
Irritable bowel syndrome
Impairments
-Knee pain
-Limited knee range of motion
-Quadriceps weakness
-Knee pain
-Limited knee range of motion
-Quadriceps weakness
Functional
Limitations
Unable to:
-squat
-kneel
-climb stairs
-jog
-jump
Unable to:
-squat
-kneel
-climb stairs
-jog
-jump
-Frequent abdominal pain and
bloating
-Chronic diarrhea
-Headaches
Unable to:
-concentrate for extended
periods of time
-sit for long periods of time
Disability
Unable to:
-play basketball
-go to classes without using
crutches
Unable to:
-work as a roofer
-play on the floor with his
young children
-maintain his home garden
Unable to:
-work as productively as she
would like as a lawyer
-participate in social activities
as she would like (e.g., no
movies, no dinners out)
Unable to:
-Serve meals at the homeless
shelter
-maintain his home and yard
as he would like
Quality of Life
-Increased anxiety because of loss
of identity as an athlete
-Loss of social support from team
members
-Increased anxiety because of
inability to work and provide
financially for his family
-Depression because of
inability to interact with his
children as he would like to
-Increased anxiety because of
inability to work as much as
she would like
-Extreme concern that she may
not make partner at her law
firm
-Loss of social role in her circle
of friends
-Increased anxiety about
having to move out of his
home because of his physical
health
-Loss of social support from
fellow volunteers at the
homeless shelter
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70-year-old male retiree who
volunteers regularly at a
homeless shelter
Early stage of Parkinson
disease
-Minor tremors
-Slowed movements
-Diminished reflexes
Unable to:
-perform upper extremity
tasks without considerable
shaking
-walk as fast as he would like
-maintain his balance as well
as he previously did
Nagi’s Model
• Active pathology: refers to the patient’s injury or illness.
• Impairment: refers to abnormality in physiological function at the site of
injury. Considered DOE.
• Functional limitation: refers to limitations in actions due to the
associated impairments. Represents DOE or POE depending on the context.
• Disability: operationally defined as an inability to perform normal socially
expected activities due to functional limitations. Considered POE.
• Quality of life: an individual’s vitality and level of satisfaction with his or
her current state of existence. Can be influenced by impairments,
functional limitations, and disability. Considered POE.
• In the context of health care outcomes, this concept is referred to as
health-related quality of life (HRQOL) to distinguish it from
socioeconomic or interpersonal issues that may also influence an
individual’s overall quality of life.
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The National Center for Medical
Rehabilitation Research
• The National Center for Medical Rehabilitation
Research (NCMRR) is a division of the United
States National Institutes of Health. NCMRR’s
disablement model is similar to Nagi’s model, but it
replaces “quality of life” with “societal limitations.”
• Societal limitations: refer to restrictions resulting
from social policy or barriers, which limit fulfillment
of roles or deny access to services and opportunities
associated with full participation in society.
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World Health Organization (WHO)
The WHO disasblement model uses a standardized documentation system
that allows clinicians and health systems to classify and quantify specific
descriptors of a patient’s disability.
International Classification of Functioning, Disability and Health (ICF) model. (Reprinted with permission from World
Health Organization (WHO).)
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World Health Organization (WHO) Model
• Patient’s health condition (at top of model): represents the patient’s
pathology in the form of a disorder, disease, or injury.
• Body functions and structures: the cause of the health condition
described in terms of abnormalities.
• Activities (at the center of the model): operationally defined similarly to
functional limitations in the Nagi and NCMRR models.
• Participation: involves the performance of activities in societal contexts.
• Contextual factors: (remaining portions of the model):
–
Personal factors: patient’s age, sex, socioeconomic status, and
previous life experiences.
–
Environmental factors: physical, social, and attitudinal
environments of patients; also include support and relationships,
attitudes, and services and policies. These can be considered at the
level of the individual or society.
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Clinician Derived Measures and
Patient Self-Report
Clinician Derived Measures
• Most health care providers routinely take measures on their
patients that could be considered clinical outcomes.
– Example: core body temperature or body mass index.
These measures represent DOE.
• When asked to subjectively assess their patient’s outcome or
level of disability, clinicians typically rate their patient’s
success substantially higher than the patients do
themselves.
Patient Self-Report
• The most common type of POE comes from outcomes
patients subjectively self-report on their current health
status.
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Global Health Measures
• Survey instruments used to assess global health status
typically focus on quality of life and disability.
– Multidimensional scales with questions that address
physical health and emotional well-being.
Examples of common global health outcomes
instruments:
• Short Form 36 Health Survey (SF 36)
• Short Form 12 Health Survey (SF 12)
• Sickness Impact Profile (SIP)
• Child Health Questionnaire (CHQ)
• Pediatric Outcomes Data Collection Instrument (PODCI)
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Condition-, Region-, or Dimension-Specific
Measures
• A large number of outcomes instruments exist to
assess patients with either distinct pathologies or
groups of pathologies.
– These instruments are designed to address
functional limitations and disabilities that are
often associated with patients who have the
specific injury or illness.
• Dimension-specific outcomes instruments are often
designed to assess a specific physical or emotional
phenomenon such as pain, anxiety, or depression.
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Single Item Outcomes Measures
• Having outcomes instruments with a limited number of
questions is advantageous to patients, clinicians, and
researchers because it eliminates redundancy in items.
• When dealing with global health, these measures
essentially ask patients to answer one question: “How are
you?”
• Often referred to as Single Assessment Numeric
Evaluation (SANE) scores.
• Other single item tools might ask patients to judge only
their level of pain or ask them if they have improved or
gotten worse since their last assessment.
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Choosing the Appropriate Outcomes
Instrument
• Two issues are critical when clinicians and researchers
select outcomes instruments to employ in clinical
practice or experimental studies:
1. Matching the purpose of measurement with the
instrument’s design.
2. Ensuring that the instrument’s clinimetric properties
have been rigorously established.
• Be careful not to overgeneralize the utility of an
outcomes instrument to populations that it was not
designed to measure.
• Clinimetric properties such as reliability, validity,
sensitivity to change, and internal consistency must all
be assessed during the development of an outcomes
instrument.
Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins
Chapter Summary and Key Points
• Disease-oriented evidence (DOE) is critical to understanding the
pathophysiology of specific conditions.
• Patient-oriented evidence (POE) outcomes measures provide
critical information regarding the impact that a person’s health
care status has on his or her ability to function in society and his
or her quality of life.
• Each disablement model provides a framework using standard
terminology for the description of health status.
• Clinician-subjective reports of patient outcomes should be
considered DOE rather than POE.
• Eliminating redundancy in items is an important step in developing
an outcomes instrument.
• Care must be taken not to overgeneralize the utility of an
outcomes instrument to populations that it was not designed to
measure.
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