Diagnosing Alzheimer's: Bio-Markers vs. Cognitive Tests

Contributed by: Dennis Fortier, President, Medical Care Corporation
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Journalists keep surprising me.

They, of all people, should be accustomed to choosing their words carefully.  However, in today's LA Times, a journalist reviewed a study comparing bio-markers and cognitive tests for their relative merits in diagnosing Alzheimer's disease, and probably misled a lot of readers with a poor word choice in the headline (below).

LA Times: Alzheimer's tests using pen and paper still the best

If a study compares two of the many possible approaches to a problem, and one approach is deemed superior to the other, then it is "better".  But it is not necessarily the "best".

In the body of the article, the words "old-fashioned tests using pen and paper" were probably chosen with much more care.  I say this because the field of cognitive assessment has made great progress in recent years using sophisticated math and computers to score test performances, and to compare performances across large databases of carefully studied patients. This has been a great imrprovement over the pen and paper approach.  But even the newer, hi-tech assessments are not the "best" approach.

The "best" approach in the practical sense, is to use all of the available diagnostic information that can be collected in a cost-effective manner.  In the process of an evaluation, routine bio-markers can rule-in or rule-out some routine causes of cognitive dysfunction and help physicians arrive at a correct diagnosis.  As for Alzheimer's disease (AD), a bio-marker that suggests AD combined with a cogntive test (be it an old-fashioned test or a more modern test), is currently the "best" approach.

I admit that the difference between the choice of "better" and "best" is subtle, and probably completely innocent.  But by choosing "best", the author framed the problem into a misleadingly small, either-or scenario, and may have given physicians and patients another reason to delay their own educational process about how to best manage emerging cognitive problems. That is sloppy journalism and it is counter-productive to the challenge we all face from the growing threat of Alzheimer's disease.