While the DSP blog recognizes the many nuances of this question, its final conclusion is: if you are going to question your mechanic about the validity of their diagnosis about your car and their recommended treatment, then maybe you should feel like you are allowed to do the same with your doctor. However, just as the practice of medicine is an art, the practice of being a patient also is an art. This is another way of saying, it would probably help you get to be where you need to be if you knew (or at least had thought about) what the right situation is to question your doctor, and what the right questions were to ask. This site, which interestingly enough I saw a billboard advertising this site while driving through an economically challenged area on Chicago's south side, will go a long way in helping you ask reasonable questions. If you're doctor doesn't want to answer these types of questions, it may be suggestive of an underlying problem in your relationship with your doctor.
One of the other many issues related to this pertain to how often your doctor is correct about his/her diagnosis. If he is right all the time, then why question, other than to pursue clarification? The DSP blog is sad to reveal that while listening to, How Doctors Think, he heard the author suggest that doctors have the wrong diagnosis 15% of the time. If you're one of those 15%, and you can pose the right questions that will make your doctor realize that maybe she should be a more uncertain of her diagnosis than she is, then you might move into the 85% category of patients correctly diagnosed.
Obviously, way more to the nuanced art of asking the right questions. Would enjoy hearing your stories about how your questions led to the right diagnosis or treatment.
P.S. There's no way a post can do justice to that question, so that's why the DSP blog shamelessly invites you to for next Saturday's show where we will explore this question further with Lisa Hall. In light of the realization of what a boring monologue/diatribe yesterday's show was (note it was so bad, I don't even link to it), I am also inviting a cohost to join me, somebody from the ranks of the patient world, somebody that can a) add some humor; b) keep it real; c) argue when necessary.
P.P.S. Example of perhaps the wrong approach to questioning doctors, from this enjoyable site: Doctor: "The best thing for you to do, is to stop drinking and smoking, get more sleep, and stay away from women." Patient: "I want to know all of my treatment options. What else would you recommend?"