Can eye doctors see if redness is caused by inflammation/allergy/dryness?

[qwertyu]

I had some doctor that said my redness was caused by allergy, another one said it wasn't allergy and instead was inflammation...

If you go to the best eye doctor in the world, not saying anything, not taking any test. Can the eye doctor with the help of a slip lamp determinate what the redness is caused by (i.e allergy/dryness)? Or is it a guess based on the things you say and test result?

[poppy]

If the doctor does not ask your symptoms/history in detail, nor perform any tests, nor monitor you over a period of time, I believe it is impossible for them to say what the cause is. The doctor is most likely to simply GUESS based on a) what is the most common cause of problems like that and b) what "diagnosis" requires them to do the least work. Even if they are thorough and do tests, the diagnosis is probably still going to be a matter of opinion, not certain.

There are many, many different causes of inflammation. Including allergies, viruses, bacteria, fungus, injury, autoimmune disorder, so many different things. Terms like blepharitis and conjunctivitis and keratitis simply mean you have inflammation in different parts of the eye. It is not a diagnosis. I don't think it is possible for a doctor to tell just with one short exam, whether dry eye is causing inflammation or is FROM inflammation (chicken or egg?) Doctors try to confuse us to get rid of us, by using terms that are NOT actually a diagnosis. We shouldn't allow them to get away with this whilst we are paying them.