Page 277 - Statistics for Dummies

Chapter 17
Experiments: Medical
Breakthroughs or
Misleading Results?
In This Chapter
▶ Distinguishing experiments from observational studies
▶ Dissecting the criteria for a good experiment
▶ Watching for misleading results
edical breakthroughs seem to come and go quickly. One day you
Mhear about a promising new treatment for a disease, only to find out
later that the drug didn’t live up to expectations in the last stage of testing.
Pharmaceutical companies bombard TV viewers with commercials for pills,
sending millions of people to their doctors clamoring for the latest and great-
est cures for their ills, sometimes without even knowing what the drugs are
for. Anyone can search the Internet for details about any type of ailment, dis-
ease, or symptom and come up with tons of information and advice. But how
much can you really believe? And how do you decide which options are best
for you if you get sick, need surgery, or have an emergency?

In this chapter, you go behind the scenes of experiments, the driving force of
medical studies and other investigations in which comparisons are made —
comparisons that test, for example, which building materials are best, which
soft drink teens prefer, and so on. You find out the difference between experi-
ments and observational studies and discover what experiments can do for
you, how they’re supposed to be done, how they can go wrong, and how you
can spot misleading results. With so many headlines, sound bites, and pieces
of “expert advice” coming at you from all directions, you need to use all your
critical thinking skills to evaluate the sometimes-conflicting information
you’re presented with on a regular basis.

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