Clinical assessment is the practice of figuring out what is wrong with a patient. In my practice, this involves asking a lot of questions, and trying to figure out from the answers what structures and functions in the body are not working as they should. Usually, people have a pretty good idea of what is going on in their body. My job, in that case, is to try to identify a pattern that can be recognized, and make a conclusion about what can be done.
Besides interviewing someone, there is the process of visually observing or palpating some part of the body to find some sign or symptom of what is going on. I have a few tools, such as a UV lamp and a microscope, that I can use to get more information if what I'm seeing with an unaided eye is not enough.
All of this is time-consuming and complicated. It requires knowing what to look for, and what patterns of symptoms go with which particular dysfunction. It requires knowledge of anatomy, physiology, and pathology, in addition to knowing what to do about a problem once it is identified. This is the hardest part of being a clinician, I think. If it were possible to avoid this step, being a healer would be as simple as memorizing the properties of a few medicinal plants.
This is why so many insincere people who put themselves forward as healers-- charlatans, if you will-- come equipped with a one-size-fits-all diagnostic technique. There are many such techniques out there, but they all have a few things in common. First, they take very little effort to learn. There may be a few rules that need to be memorized, but no real thought has to go into the process. Secondly, they are not very time consuming. Thirdly, the same technique works for an amazing variety of different conditions. These techniques allow people without skill or discipline to pretend to be healers. Unfortunately, they are not effective, except to fatten the purse of the practitioner. They form the body of practices that I like to call hocus-pocus-diagnosis.
First and foremost among these techniques is something called "muscle testing" or "applied kinesiology". It consists of having the patient hold a medicine in one hand (or think about a procedure, or ask a question) while holding the other hand out straight. The charlatan then presses down on the arm that is being held out straight. If the arm remains straight, this is taken as a "yes" answer; if it bends, this is taken as a "no". There is, as far as I can tell, no reason in the world why this would work (except perhaps as a gauge of how the person being questioned feels about the question). But even if there were, this would be so subject to bias and tampering that it would still be completely unreliable. I have a hard time understanding how a grown adult can stake their health and well-being on something like this, but many do.
A second technique is iridology. This involves looking at the iris of the eye. Different lines and spots in different parts of the iris are assumed to correlate to weaknesses in different organs or tissues of the body. At first, this may even sound plausibe; after all, there are things that can happen in the body that will affect the appearance of the eyes. However, the idea that each area of the iris is uniquely and specifically linked to a different organ or tissue elsewhere in the body, is a little too convenient. It would be nice if iridology were real, because it is non-invasive and easy to perform. And yet, in clinical trials, "iridologists" have consistently been unable to tell the difference between the irises of people with chronic organ failure, and those of healthy people. The sad truth is that most of the color variations in the iris are no more significant than freckles on the nose, and iridology is just a system that one person dreamed up and others imitated.
A newer and more recently popular technique, is the "scanning machine". These have different names and come from different sources. Some of them cost upwards of $10,000 for the practitioner to buy (suggesting that the people who buy them probably do believe they work). The idea is that you hook the machine up to the patient (or sometimes put a sample of blood, hair, or whatever on or into the machine) and it gives a readout telling everything that is wrong with the person, be it their heart, brain, intestines, or the presence of some rare tropical parasite. Some of these miraculous devices go a step further, and actually treat the maladies that they discover. A few even claim the ability to treat patients who are not physically present.
Now, I can believe that fairy folks live in old oaks, or that there's gold at the end of the rainbow. But some things are just beyond believing. If such a machine really existed-- even one that only did the diagnostic part-- and it only cost $10,000 or even $100,000, every hospital and large clinic would have one. The inventor would win every nobel prize in existence, and many of the world's ills would be at an end. But alas, there is no such thing. I have personally seen patients who were "diagnosed" by these machines to have african parasites, HIV, and a host of other ailments that they did not turn out to possess. One of them was once taken apart by a computer scientist from microsoft, who loked at tis source code and found that all it did was generate random results.
These are just a sample of the hocus-pocus diagnostic techniques that can be found around town. Some of the people using them may really believe they work. Others are just wanting a quick and easy way to charge people for something, to capitalize on fear and suffering.
For my part, I don't do "diagnosis". This word means "certain knowledge" in Greek, and I don't think there's any such thing when it comes to healthcare. I believe in assessment based on real information, and keeping an open mind to the fact that things can change, or new information can come forward.