Definitely call them and ask. But sometimes the answer are obvious and the usual answer is "Its very competitive out there". For me, I ask starting from GPA, DAT, interview, experience, pre-requisites and community service.
i would say call and ask nicely. if you didn't get in anywhere else you can ask on the lines of 'i would really like to attend **** school and am planning to apply next year. how can i improve my application?'
Small seat + A lot of qualified students + We look all aspects of applicants.......
In my case, I think some schools really like my extracurricular activities, whereas other schools don't like mine.
During your interview, you should let them know more about yourself. Just ok interview is highly not likely to be enough!
But they may point out areas where you really should improve for next cycle. Such as your DAT score was low compared to our other applicants so think about retaking it, or the committee is unsure of how you can handle advanced science classes you may want to take such and such class to sway their opinion.