It is well-known that manufacturers of devices (lasers, IOLs, etc.) cherry-pick the so-called top surgeons for clinical trials. It's also well-known that surgeons cherry-pick patients for these clinical trials, including only patients who are likely to have the best outcomes. This is one reason why clinical trials do not really reflect the outcomes that will be seen in the real world in the hands of average surgeons and borderline patients. Let's "listen in" on an FDA panel meeting:

http://www.fda.gov/ohrms/dockets/ac/03/transcripts/3991t1.htm

Quote:

DR. WEISS: I think we have to be careful about this best physicians talking about lack of data. I'm sure these were good docs and good surgeons, but creating this extra godlike category, I think we should take out of the discussion.

DR. BANDEENROCHE: That's a point welltaken. That's a point welltaken. Nonetheless, I mean, we hardly expect better performance in the field than we do in a clinical trial.

DR. McCULLEY: You don't have data to support that statement, do you? Do you have data to support that statement? You do. Okay.

DR. ROSENTHAL: With all kinds of devices.

DR. McCULLEY: All right.

DR. WEISS: What I would then like to lead to is since there's agreement ‑‑

DR. ROSENTHAL: Wait.

DR. WEISS: Yes.

DR. ROSENTHAL: I want to make sure I said the right thing. Once they go out in the field, they tend to have more problems than they do within the clinical trial.

DR. McCULLEY: But you don't have data to support that the people who do the trials are the best of the best.

DR. ROSENTHAL: No.

DR. McCULLEY: I think that is opinion ‑‑

DR. MACSAI: That's my opinion.

DR. McCULLEY: That is Marian's opinion, and it should not be in our discussions.

DR. WEISS: So we're going to take out the "god" factor out of the discussion.

(Laughter.)

Notice how Dr. Rosenthal, Division Director, tried to back up and cover his tracks because he let that comment slip out.