Friday, February 15, 2019

Utility-weighted modified Rankin Scale: Still too crude to be a truly patient-centric primary outcome measure?

I can't tell what this actually is but it has been out for 5 years already. But since the original Rankin scale was totally subjective and pretty much useless I don't see how this improves things.  Until we get to an objective 3d damage diagnosis, location and size of dead and damaged neurons, we will never get to rehab protocols based on factual objective criteria. Until then your doctor and therapists are completely guessing what needs to be fixed. 

See this example of nine reasons for a movement disability:

You can't tell me these all have the same solution, I'm not that stupid.
1. Penumbra damage to the motor cortex.
2. Dead brain in the motor cortex.
3. Penumbra damage in the pre-motor cortex.
4. Dead brain in the pre-motor cortex.
5. Penumbra damage in the executive control area.
6. Dead brain in the executive control area.
7. Penumbra damage in the white matter underlying any of these three.
8. Dead brain in the white matter underlying any of these three.
9. Spasticity preventing movement from occurring.
First we need an objective 3d damage diagnosis, without that there is no point in going forward. Dr. Watson likely to the rescue. 

 

A Utility-Weighted Modified Rankin Scale: Derivation and Application to Completed Stroke Trials (P5.008)

April 2014

 

Utility-weighted modified Rankin Scale: Still too crude to be a truly patient-centric primary outcome measure?

First Published February 12, 2019 Research Article
The utility-weighted modified Rankin Scale (UW-mRS) is an outcome measure recently proposed to improve statistical efficiency and interpretability of the mRS. Statistical properties of the UW-mRS have been well investigated, but construct validity has yet to be established.
To investigate the construct validity of the UW-mRS as a primary outcome measure by assessing variability in utility values within and between mRS categories, over time post-stroke, and by different derivation methods.
UW-mRS was derived using assessment of quality of life (AQoL-4D) and mRS scores at 3 and 12 months (n = 2030) from a large randomized controlled trial, A Very Early Rehabilitation Trial (AVERT). Receiver operator characteristic (ROC) analysis of AQoL-4D was conducted to differentiate between sequential mRS categories. Intraclass correlation was used to explore variability in utility values over time post-stroke, UW-mRS values, and derivation methods from multiple studies.
UW-mRS values for mRS categories 0–6 at three months were 0.80, 0.78, 0.63, 0.37, 0.11, 0.03, and 0. Based on AQoL-4D utility values, areas under the ROC curve varied from 0.54 to 0.87. Time post-stroke explained 42%–56% of variability in AQoL-4D utility values in patients with no change in mRS between 3 and 12 months. The choice of the derivation method contributed to 25% of the variability in UW-mRS values. (Whatever this gobbledegook means. Obviously not meant for layperson survivors. If you can't explain this to normal people you have failed in your research.)
The high variability in utility values between and within mRS categories, over time post-stroke, and using different derivation methods is not adequately reflected in the UW-mRS. These threats to construct validity warrant caution when using UW-mRS as a primary outcome measure.
Australian New Zealand Clinical Trials Registry (ACTRN12606000185561

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