I work with many fields of study at my organization establishing manning and balancing processes. My methodologies are very sound and proven mathematical approaches: queueing theory, line balancing, takt time analysis, etc. Most fields are very receptive and can follow the math/analysis and either agree or state understandable issues with the analysis. In short, most all fields at least have a desire to understand and improve their processes.
It seems through my experience, when dealing with medical personnel I cannot even get them to listen to any recommendations much less implement them. I have had several friends in the medical field tell me flat out that no one is going to listen to me because I'm not a doctor. This is very frustrating for my job. It also looks poorly on me because whether or not they implement the suggestions, if there is no improvement then I did not accomplish what was tasked of me. Even if I point out their reluctance, I am still on the defensive which is not a strong position to be holding. It is also a large blow to morale and ends up wasting much of my time.
Are there any tactics to deal with unreceptive people in general when they will not even attempt to rationalize or work with you?