Before we had EBM (evidence-based medicine) we had another kind of EBM: experience-based medicine. Mark Crislip has said that the three most dangerous words in medicine are 'In my experience.' I agree wholeheartedly. On the other hand, it would be a mistake to discount experience entirely. Dynamite is dangerous too, but when handled with proper safety precautions it can be very useful in mining, road-building, and other endeavors.
When I was in med school, the professor would say 'In my experience, drug A works better than drug B.' and we would take careful notes, follow his lead, and prescribe drug A unquestioningly. That is no longer acceptable. Today we ask for controlled studies that objectively compare drug A to drug B. That doesn't mean the professor's observations were entirely useless: experience, like anecdotes, can draw attention to things that are worth evaluating with the scientific method.
We don't always have the pertinent scientific studies needed to make a clinical decision. When there is no hard evidence, a clinician's experience may be all we have to go on. Knowing that a patient with disease X got better following treatment Y is a step above having no knowledge at all about X or Y. A small step, but arguably better than no step at all.
Experience is valuable in other ways. First, there's the 'been there, done that' phenomenon. Older doctors have seen more: they may recognize a diagnosis that less experienced doctors simply have never encountered. My dermatology professor in med school told us about a patient who had stumped him: she had an unusual dermatitis of her hands that was worst on her thumb and index finger. His father, also a doctor, asked her if she had geraniums at home. She did. She had been plucking off the dead leaves and was reacting to a chemical in the leaves. The older doctor had seen it before; his son hadn't.
Then there's what we loosely call 'intuition.' It can be misleading, but it can also be a function of pattern recognition that has not risen to the level of conscious awareness. Experience can help us perceive that 'something just isn't right' about a patient or a working diagnosis. An experienced doctor may get a feeling that a patient might have a certain disease. He couldn't justify his hunch to another doctor, but he has subconsciously recognized a constellation of findings that were present in other patients he has seen. Of course, he would still need to do appropriate tests to confirm the diagnosis, but he might do more tests and do them sooner than a less experienced doctor. This kind of pattern recognition has been called the 'Aunt Tillie' phenomenon: you can spot your Aunt Tillie's face in a crowd, but you couldn't tell someone else how to do it. You just know Aunt Tillie when you see her. Computer face recognition is learning how to do this, but it uses measurements, not the gestalt method our brains use.
Then there's the wisdom that (sometimes) comes with age. I've just been reading Marc Agronin's book How We Age where he shows that old age is not all bad. As we get older, we are not able to accomplish mental tasks as fast, and our short-term memory declines; but there are compensations. We are more able to integrate thinking and feeling, less likely to get carried away by emotions, better able to see both sides of an issue, and better able to cope with ambiguity. We can develop more patience, acceptance, tolerance, and pragmatism in dealing with complex situations. We have a vast store of life experiences to bring to the table, helping us put things into a more realistic perspective. Wisdom is elusive: not every elder develops it. I'm sure you can all think of many counterexamples.
Medicine is an applied science, and the same science can be applied in different ways by different doctors. There are times when two science-based doctors can look at the same body of evidence and still disagree about what it really means or about what to do for a specific patient. There is room for disagreement and for different approaches. Scientific medicine is often criticized for focusing on the disease rather than on the person who has the disease. I have known patients who have turned to alternative providers because of a bad experience with a science-based doctor's poor communication skills or 'bedside manner.' We can aspire to a kinder, gentler, more personal science-based medicine where experience and improving people skills are integrated with science (a kind of 'integrative medicine' that actually makes sense.)
It's not clear whether you are better off with a young doctor or an older one. A young doctor is more likely to be up to date on the latest science; an older doctor might make better patient-centered decisions. A younger doctor might be better at tuning up your bodily vehicle; an older one might be better at helping you decide when to drive it, where to go, and how fast. A young doctor might offer the latest treatment; an older one might question whether it is really preferable to an older treatment for that particular individual, or even question whether any treatment is really necessary at all.
In summary, while 'in my experience' claims can be dangerous, experience does have a role to play in science-based medicine.
As an ORF (Old Retired' something) and a Medicare-card-carrying senior citizen, I am biased. I have a vested interest in thinking that I have improved with age and experience. This is an opinion piece and I can't cite any controlled studies to support my opinions. I'm almost tempted to insert tongue firmly into cheek and say 'Trust me; I'm a doctor.'