6075_What are clinical neurological outcomes - Naidech
Andrew Naidech
Andrew:
1
Hello, and welcome to this discussion on what are clinical
neurological outcomes with me, Andrew Naidech.
Good
neurological outcome measures are clinically meaningful. Such as
the ability to walk, the ability to manage a household, and other
meaningful activities. What is a good outcome may change with
the perspective of who is measuring it. For example, pairs may
wish to minimize the cost of care. Healthcare providers may wish
to maximize billing. Patients may wish to maximize their quality
of life outcomes. And caregivers may wish to reduce the effort
required to perform a daily task.
Good outcome measures should be valid, meaning they should
measure what they purport to measure, and good outcome
measures should be reliable. Repeated scores should give similar
measurements.
Clinical research and comparative effective
research are extraordinarily difficult without outcomes. Especially
outcomes obtained after discharge. Many clinical effectiveness
studies use administrative data sets for which clinical outcomes are
difficult or impossible to obtain and instead involve other
outcomes that may be found in large data sets, such as the filling of
prescriptions or searches of dissidence from the Social Security
Death Index.
Once in hand, you can often go back and get other data from the
in-patient medical record later. Such as medication used or vital
signs. You can get some clinical data retrospectively. For
example, the NIH Stroke Scale has well established to be reliable
for chart abstraction, but functional outcomes, like the modified
ranking scale, cannot be assessed accurately from clinic notes.
There’s a limited number of current validated outcomes, and many
of these are disease-specific. Some of these may be expensive,
such as imaging studies, and not routinely available.
Consensus conferences or Meta analysis will use the outcomes
found in all data sets as a lowest common denominator. So
comparative studies using sophisticated outcomes are usually not
possible.
This slide shows a variety of clinical outcome scales and data for
comparative effectiveness research often found in neurologic
studies. Examples of ordinal scales are the modified ranking scale,
the Glasgow outcome scale, and its extended version, the EDSS,
and so on. The advantage of these is that they generally have interreviewable liability, and are easy to obtain. Unfortunately, there
www.gmrtranscription.com
6075_What are clinical neurological outcomes - Naidech
Andrew Naidech
2
are minimal cognitive and social assessments, and these measures
are not specific.
Mortality is a readily identifiable outcome, easy to obtain in-house
from medical records and if the patient has a social security
number, can be obtained from the Social Security Death Index.
Unfortunately, mortality is a crude endpoint. The NIH Stroke
Scale is a standard, validated, neurologic exam. It has a very high
inter-rative reliability, is clinically useful, and can be completed in
a few minutes. The downside to the NIH Stroke Scale include the
fact that you can do it in person only. The exam is incentative in
coma, and there’s a minimal assessment of cognition and no
assessment of social functioning. The sickness impact profile is
one of a series of long questionnaires. These questionnaires are
comprehensive but are tedious to perform.
The Barthel Index is a more comprehensive assessment of
activities daily living, but take somewhat longer time to assess.
Payors, hospitals, and providers are keenly interested in length of
stay, which can be abstracted from the hospital database. The
length of stay correlates with the cost of care, an important metric
in the current environment. Unfortunately, length of stay is not
specific and is related to complications of care as much as the
index condition, itself.
The rehabilitation literature favors the functional independence
measure and measures like it. These are comprehensive but are
time-intensive, taking close to 30 minutes per patient. NIH patient
reported outcomes measurement information system, or PROMIS,
and Neuro-QOL are designed to be entered on the web, although
they can be entered on paper. Neuro-QOL is validated for proxy
entry endorsed by NIH. And these provide numeric scores which
are validated to the US general population. The downsides of
Neuro-QOL include the need for someone to report outcomes, and
there are few comparative data in the literature compared to the
standard ordinal scales.
There is a continuum of outcomes that are reported by the patient,
outcomes that are assessed by certified healthcare staff, and
outcomes in the middle. Patient reported outcomes include
questionnaires like the Sickness Impact Profile and Neuro-QOL.
These depend only upon what the patient or proxy says is
happening, with no room for influence from healthcare staff or
research staff. The advantages include a flexible method of entry.
www.gmrtranscription.com
6075_What are clinical neurological outcomes - Naidech
Andrew Naidech
3
Neuro-QOL has preferred methods of entry on the web, in addition
to on paper.
An example of a certified examiner’s score is the NIH Stroke
Scale. It is a highly reproducible, standardized exam that does not
influence at all by how the patient feels he or she is doing. These
have the downsides of examination space and the need for
validated staff to perform them. In the middle somewhere are
validated interfusing questionnaires for scales such as the Modified
Rankin Scale, where there’s an investigator assessment of what the
patient reports they are doing. Validation studies may link these.
For example, Sickness Impact Profile and Neuro-QOL have been
shown to be tightly associated with the Modified Rankin Scale,
and the Modified Rankin Scale is tightly associated with the NIH
Stroke Scale.
Of particular note, administrative electronic records will contain
outcomes but may not contain these outcomes that require direct
patient contact unless they are specifically documented. We use
the Modified Rankin Scale as an example of a widely used ordinal
outcome scale. The Modified Rankin Scale is the primary
outcome for hemorrhagic and ischemic stroke, and is also used in
studies of survivors of cardiac arrest and in brain trauma. Other
scales, such as the EDSS for multiple sclerosis, are more similar
than different, and generally have a scale from excellent outcome
with no symptoms, to severe dependence and death.
Common to all ordinal scales, there’s often a cut point in which the
outcome is considered good or poor. And where this outcome line
is drawn depends upon the condition you are studying and how
severely affected the patient population is. For more on how these
outcomes might be chosen and the analysis that accompanies it,
please see the next slide deck on analyzing neurologic outcomes.
The Rankin scale and other ordinal outcome scales usually are
greatly focused on mobility. Mobility is very important, but is an
incomplete identifier. Other outcomes, such as the ability to
manage one’s own finances, maintain a household, care for family
members and so on, are generally not as well assessed in these
ordinal outcome scales.
Of particular note for cognitive
assessment, see the NIH Toolbox, a standardized set of neurocognitive assessments.
www.gmrtranscription.com
6075_What are clinical neurological outcomes - Naidech
Andrew Naidech
4
So we’re returning to the Modified Rankin Scale. Let’s use these
two examples. In the upper right is a picture of Franklin Delano
Roosevelt, president of the United States during World War II. He
was paralyzed at this time from the sequella of polio, a fact that
was hidden from the American public due to a compliant press
corps. He was not independent for activities of daily living. And
if you visit the Roosevelt estate in Hyde Park, you can still see his
old antique car with a specialized device that would dispense lit
cigarettes that he could enjoy while driving; well worth your time
in upstate New York. FDR’s not independent for activities of daily
living and is a Rankin 4.
Below him is an actor from AMC’s winning series The Living
Dead. Zombies generally have social impairments. Their friends
and coworkers no longer want to see them, but they do ambulate
and are able to perform activities of daily living, or un-living as the
case may be. This zombie is a Rankin scale of 2. While to some
extent the example’s a bit absurd, it does illustrate that social and
cognitive functioning may not be well assessed by the Modified
Rankin Scale. The zombie has a better Modified Rankin Scale, but
FDR certainly had the better health-related quality of life.
This is a key advantage of Neuro-QOL, which now contains over a
dozen validated instruments and item banks for quality of life,
divided into mental, social, and physical categories. The current
slide shows Neuro-QOL as it now stands. Updates are regularly
provided on the website: neuroqol.org. Which domain of quality
of life you choose as your primary outcome depends upon your
study, your patients, and the hypothesis you wish to test? You may
also wish to consider assessing multiple domains for a
complementary assessment. For example, applied cognition and
mobility and sleep disturbance, depending on your population.
Thank you so much for your attention with this webcast. We
acknowledge the NIH and its generous support of Neuro-QOL.
You may wish to watch the next video in the series: How Does
One Analyze Neurological Outcomes.
[End of Audio]
Duration: 10 minutes
www.gmrtranscription.com