Let's assume that we want to design a
medical research on cancer: we set up an experimental and a control
group, made up of 50 individuals each, and we check their health for
a certain period of time, let's say, 25 years. We order the members
of the experimental group to say “Merry Christmas!” as soon as
they get up from their bed every day in the morning; members of the
control group should say nothing. After 25 years we compare the
results. Let's imagine that 2% (1 out of 50) of people belonging to
the first group died of cancer, whereas the amount of people
belonging to the control group who died for the same reason is 10% (5
out of 50).
Conclusions: saying “Merry Christmas”
every morning reduces the risk of cancer disease.
What a nonsense, you may say. Indeed it
is. Unfortunately it's not unusual to find similar mistakes in social
and medical researches. Actually the real mistake rests often in the
the interpretation that journalists, especially those with limited
knowledge of methodology of social and medical research, give to such
studies. The recent news about beer, women and heart attack is a
clear example of this approach. A Swedish study, based on data
collected over a 32-year period on 1462 participants, found that
women who drank moderate amounts of beer were at a reduced risk of
getting heart attacks. Online news magazine jumped immediately to the
following conclusions:
Why women should drink beer: Two
pints a week slashes the risk of heart attack by a third
(DailyMail)
Women who drink 2 pints of beer a week cut heart attack risk by a third
(Mirror UK)
As a matter of fact, things are not as
straightforward as these headlines claim. The Swedish researchers
simply made a correlation of two things (namely: drinking beer and
suffering from heart attack), but such correlation can be arbitrary
(just as believing that saying “Merry Christmas” every morning
has the power to avoid cancer). It is possible that, among the women
who drank and didn't have heart problems, a considerable amount of them went to the pub on foot. In
this case, what might have prevented them from suffering from heart disease was
not the drinking, but the physical activity. We can also assume that
those who drink have a more social active life, which is an index of
healthy lifestyle. It's not my intention to put down altogether the
Swedish research. I'm just saying that we cannot come to convincing
conclusions based on a relatively small study like this one
(featuring less than 1500 participants in a limited geographical
region). The fact that enthusiastic online journalists trumpeted the
study results (probably without even reading the whole research) and the
benefits of beer, shows three interesting things:
1) alcohol
lobbyists are powerful and always on the lookout for new groups of
consumers. Now it's the turn of women (by the way, I am sure a
new sensational study on the benefits of alcohol on pregnant women
will follow soon...)
2) I detect here a certain disapproval
towards people who promote healthy lifestyle and try to highlight the
danger of drinking alcohol. For instance, I read the news following a
link on FB. The link was posted by some FB female friends of mine who
celebrated the good (?) news as a “slap in the face" to those who
claim that drinking alcohol is always unhealthy. Such misleading news
hit considerably the ego of those suffering from “cognitive
dissonance” (a situation involving conflicting attitudes, beliefs
or behaviors: drinking is dangerous vs I like drinking).
3) Beer, wine and alcoholic beverages are very popular in our society, therefore many people don't accept the fact that their consume brings poisoning effects on our body and mind, even if it contributes to specific economic sectors (but causes even larger losses on health budgets).
