One of the most difficult messages to get
across to an average health-conscious person, especially an aging one, is that
screening tests are not necessarily always benign.
Or putting that in another fashion: while
not dangerous in themselves, lots of screening tests can – and do - result in
ultimate harm to the person who had one.
That comes mainly from “false positive”
results, which occur much more often than many people realize, and certainly
much more often than doctors are generally willing to admit.
The harm from false positive results in
screening tests comes from two sources: potential physical harm (biopsies are
surgical interventions, and there is no such thing as risk-free surgery) and
equally important, from psychological effects, although that side of things is
often neglected or rejected as a minor concern., which it decidedly is not for
many people.
That came home in a pretty stark fashion
this week from a report in the March/April issue of The Annals of Family Medicine in which Danish researchers concluded
that a small but substantial number of women who receive false positive reports
from a mammogram are adversely affected by psychological problems for up to 3 years
following that report.
Now it may only be a small number of women
who are affected in that way, but given how common mammograms are and given how
often they result in false positives (another report this week estimated that
in some young women with dense breasts, the false positive rate for mammography
can be as high as a whopping 60 %), the total number of women who suffer these
adverse consequences is consequently huge, and we really don’t know that
ultimate cost.
Now, it has to be stressed that on the very
important other hand, mammograms do save some lives (although the number of
lives saved by mammography is a constant topic of debate among the experts), so
this should not dissuade anyone from getting a mammogram: it should just be
something that every woman adds into the mix of things she has to consider
before automatically getting such a test.
And what is true of mammography is also
true for many (most?) other screening tests as well.
