Medical Diagnosis: How doctors analyze symptoms to make diagnosis

Doctor Sapkota talks directly to patients and explains how medical symptoms and diagnosis are related. Visit http://symptomsdiagnosisbook.com for details

Video transcript:
Normally people think making diagnosis from symptoms is like a matching game. Let me explain what I mean by that. When someone famous gets diagnosed with a disease the media talks about that disease a lot. But what exactly do they say? They repeat the same pattern. They invite doctors and experts to TV and ask, "what are the symptoms of this disease?" For example, let's call it disease A. All they talk about is how disease A have these 4 symptoms. Let's call them symptom 1, symptom 2, symptom 3 and symptom 4. What do people learn from that news? People learn that if you have the combination of these 4 symptoms, you have disease A. They also learned that if someone has being diagnosed with disease A, that person is likely to have these 4 symptoms. But, is that true? What if you have 2 out of the 4 symptoms? Do you then have a fifty percent chance of having that disease A?
Now let's look at the bigger picture now we have three diseases to compare. Each disease shares some common symptoms with the other but has a unique set of symptoms. Now if someone has symptom 1 and symptom 4, does that person have disease A or disease B? If someone has symptom 2 and symptom 3, does that person have disease A or disease C? The more important question is: if someone has an exact match, is that person more likely to have that disease than the disease with incomplete match? For example, if someone has the combination of symptoms 1, 2, 3 and 4 can that person still have disease B or disease C? So how do we decide? Where is the missing factor?
The most important factor, the one that you should look at first, and the one that is almost entirely absent from these discussion and completely ignored by talking heads on TV is the patient. Analysis of any symptom must start from the patient. All these factors associated with the patient matter.You need to know that person very well before you try to make any sense of symptoms in that person. So, what are a few things about the patient that influences how symptoms appear in that patient? The age of the patient, the gender, the body mass index, occupation, level of physical activity, life experiences, smoking habits, alcohol use, history of any prior medical problems and even the personality of that patient matter. After you know your patient very well you move on and analyze the particular symptom in detail, not just take that symptom on it's face value to make the diagnosis. So, you ask where exactly it started, what kind of pain was it, what made it worse,what made it better, how long did it last and whether it was a constant or intermittent. All these details and the patient factors give us a picture and help us decide what could be going on inside the patient's body and this is how we make the diagnosis.