The diagnosis cloud

Data Clouds

I've looked at clouds from both sides now
From up and down and still somehow
It's cloud's illusions I recall
I really don't know clouds at all

Judy Collins

All real world, "scientific" information comes as a cloud.There is a penumbra of uncertainty that surrounds every "fact"  Even physical constants, like the  universal gravitational constant, G,  are never quite exact because of measurement issues.  Data in medicine is usually very inexact.  Accumulation of large samples is the standard method for improving the resolutions; but more data always leads to more cloud.  The kernel of truth is always shrouded, the veils  are too thick.  The truth is imagined be a point of light, encased in translucent noise,  A more sophisticated ( but, perhaps no more correct) view is that the truth, itself is a cloud.  Perhaps the Heisenberg Uncertainty Principle  ( there is an absolute limit to the accuracy of a measurement) also applies to  medicine

 Treatment depends upon definition.  The definition of  diseases has a significant  traditional component.  The diseases of the Bible, Hippocrates and Galen are now understood  to be mixtures of entities.  The signs and symptoms that these extraordinary ancient observers  could identify come from a variety of very different processes.   To them, jaundice was a disease entity.  We understand that jaundice, yellow discoloration of the skin and eyes, can be the result of liver disease, diseases of the red blood cells, gallstones, etc.  We can identify these differences using biochemical  blood tests, the microscope and CT scans.

 As I say this, I am reminded of a Saturday Night Live skit from the 1970's,  Theodoric of York, Medieval Barber. In that clip, the medieval medical practitioner reassures the patient's mother by talking about how medical science had progressed from ideas of demonic possession to understanding that disease is caused by imbalance of humors.brought on by toads  How ridiculous will our models look in 50 years? 

The models of disease  that emerged in the nineteenth century, with  the application of the microscope  and the use of dissection emphasized a cellular basis of disease.  The discovery of pathogenic bacteria led to a simple model of infection that continues to be the basis of the greatest of medical interventions.  In the current era, most diseases  are still viewed  through the lens of the light microscope.  The incorporation of molecular and interactive (immune)  information has lagged.
It is hard to improve upon success. But we, who care for the sick, understand the challenge; we see how limited is this success. 

Current imaging, blood tests, and microscopic techniques give us a working understanding of the varieties of disease processes.  It has led to real advances. The main block to further success has been the  limited treatment options.  The improved vision afforded by molecular and immune systems techniques will give us a better understanding  of the disease process and  lead to improved outcomes.  These are radar that will penetrate some of the clouds.