I’m in Israel, home to some of the most innovative care in the world.  Doctors here wanted to know if the high-tech tests that are an increasing part of their work help.  A couple of weeks ago, they published their results.

It turns out that in about 90% of cases, it didn’t matter.

A physical exam, the patient’s history, and the basic set of tests that doctors have done for decades was almost always all that was needed to get a diagnosis.  As one of the doctors in the study put it, “basic clinical skills remain a powerful tool, sufficient for achieving an accurate diagnosis in most cases.”

The conventional wisdom is that doctors – at least in the U.S. – order extra tests to protect themselves from getting sued.  But this study was done in Israel, where the problem of medical malpractice is nothing like it is in the U.S.  American-style defensive medicine can’t be the reason doctors in Israel use so many diagnostic tests.

Instead, the answer is revealed in a comment from a Canadian doctor who wasn’t involved in the study.  According to him, the use of high-tech studies has become so “routine” that doctors need to be reminded that they aren’t a replacement for actually diagnosing the patient.

There is something more fundamental happening – and it’s happening around the world.

To understand it, look to something that is happening in courtrooms across the U.S.  Some call it the “CSI Effect,” after the TV show, CSI.  In that show, a police team uses sophisticated technology to identify criminals with almost complete certainty.  Researchers have found that shows like CSI have changed jurors’ expectations of what kind of evidence the prosecution should be able to present.

Something like this is happening in medicine.

Patients show up with the expectation that the doctor will use sophisticated technology to get a quick diagnosis.  They’re often surprised to see how it really works.  Their doctor is rushed, uses paper files, and it can often take a long time before you get a clear diagnosis.  Doctors often order high-tech tests because patients expect it.

But doctors also do it because they are so pressed for time – because a test is a convenient short-cut that might reveal the answer without having to go through the trouble of asking questions, spending time with the patient, studying their medical history, and thinking about the meaning of more routine test results.

So are doctors lazy?  Do patients have overblown expectations of what doctors can really do?  Maybe.  But there is a more important truth which studies like this help reveal.

The most valuable piece of equipment your doctor has is his or her brain.  High-tech tests may give more information, but they are no replacement for your doctor’s training, judgment, and insight.

Evan Falchuk is President and Chief Operating Officer of Best Doctors.

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