Analyze the following study according to the criteria set by your instructor:
Dr. Dean Ornish, of the University of California San Francisco Medical School and Pacific
Presbyterian Medical Center, wanted to learn whether lifestyle changes could reverse the
progress of heart disease. At first, he found little support for his research, and several of
his grant requests were turned down. Eventually he secured funding from private
contributors.
Ornish recruited forty-three men and five women, ages forty-one to seventy-one, all with
very serious heart disease. A statistician randomly assigned the subjects either to a group
that followed their own doctor’s recommendations for diet and lifestyle changes or to a
group that would follow a mild exercise regimen coupled with stress-management
counseling and a low-fat vegetarian diet with no meats, poultry, or fish and with restricted
intake levels of cholesterol and fat.
Six people in this group did not complete the testing. Among the remaining twenty-two
participants, eighteen showed reversal of the blockages in their coronary arteries after one
year. In the comparison group, one person dropped out, and ten of the remaining nineteen
developed measurably worse heart disease, while three showed no significant change. Six
people in the comparison group showed measurable reversal. This was due, says Ornish,
to the lifestyle changes they made on their own.
Dr. Alexander Leaf, former chairman of the Department of Preventive Medicine at Harvard
University Medical School, says, “For the first time, we have a carefully done scientific
study that shows, even in advanced stages, this disease can be reversed with lifestyle
changes.” Ornish’s findings have prompted sizable grants from the National Heart, Lung,
and Blood Institute and other foundations.
—Adapted from
Reader’s Digest
Answers will vary