The Principles of Diagnosis
The human body is a physical system. When the system is stable(keeps functioning autonomously), it is said to be in HOMEOSTASIS or EQUILIBRIUM.
Consider balancing a pencil on your finger. That’s your body system. You blow air to one side, and you will see the pencil shaking. However, you will still balance the pencil by adjusting your finger.
Every time you blow and readjust, there is a displacement of the pencil. This is called a STRUCTURAL or PATHOLOGICAL anomaly. A structure is permanent like a building.
Then there are finger shaking for balancing every second. This is the FUNCTIONAL or PHYSIOLOGICAL anomaly.
When finger pain increases in an effort to balance(SYMPTOM), you go to the doctor.
There may be no wind or pencil shaking. But you somehow may feel that it is shaking. It is all in the mind or PSYCHOLOGY.
So the doctor has to first be sure that there are anomalies. This is called SCREENING. He then INVESTIGATES through tests and questions and asks you to OBSERVE the changes.
PATHOLOGICAL TESTS give structural changes in the body whereas PHYSIOLOGICAL tests give functional changes. A DIAGNOSIS is the confirmation of a SPECIFIC ANOMALY or DISEASE.
Disease Diagnosis=
Symptoms➡️Screening➡️Detection➡️Investigation➡️Monitoring➡️Diagnosis Screening is used to detect if there is anything wrong with the body in the first place and possible anomalies. Once an anomaly is screened, it needs to be determined whether the anomaly was an exception/response to some temporary requirement of the body or if the anomaly is more consistent.
This is done by a period of observation when the condition is monitored. Just an anomaly doesn’t mean the need for treatment. Only when the condition is observed consistently, there is a need for treatment. Then the clinician needs a diagnosis.
A diagnosis is a term used to confirm a clinical condition or disease through different evidence. The evidence that is commonly used is- Physical Examination, History, Questions, Pathological Tests, Stress Tests, or response tests.
Furthermore, diagnosing a clinical condition isn’t enough. The clinician needs to also understand the mindset of the patient. For example, even an early diagnosis of cancer makes the patient stressed just by the name.
It is also very important for a clinician to know the genetic predisposition or family history.
Therefore,
The components of diagnostics are:-
Diagnostics=Physiology+Pathology+Psychology+ Physical Examination+ History+ Questions+ Family History