When I had blood tests done, I was able to call and get the results, but they wanted me to come in to figure out what to do next (all the blood work came back normal, which left us with no easy explanation for the initial problem that made them do the tests).
I've found that it varies by surgery. At my old one, they wouldn't give you the results by phone at all. You had to either make an appointment (they wouldn't call to tell you things were back) or wait for their letter in the post.