Monday, August 06, 2007

Ideology and the Lessons still unlearned

People sometimes wonder what is meant by ideology and just how does that affect the use of science in public policy. Surely, if we have the science, ideology has nothing to do with things, right?

Sadly, no. Ecomyths are the result of ideology and the continued imposition of beliefs despite the scientific evidence that contradict those beliefs.

A good example is well explained here. It is the situation in Britain where a program was introduced into schools to promote healthy eating by giving kids a free fruit or vegetable serving each day. The follow up evaluation showed the program had no long term influence on the eating habits of children. Yet, despite the data clearly showing the program to be a massive (and expensive) failure, the academics conducting the evaluation recommended that the program be expanded, rather than cancelled.

Their thinking? Everyone knows fruits and veggies are good for you, kids have to eat right and if this program hasn't worked, then we will just double our efforts until it does. If at first you don't succeed, try, try, try again. (Especially easy when it's the government's money you are spending and you get to be a recipient).

This is ideology, not science. The science has just shown the program to have had no behavioural effect. Moreover, its starting premise also is flawed, as the most well-conducted studies following hundreds of thousands of people for decades continue to show "no relationship between fruits and vegetables and cancer and no statistically significant associations with major chronic disease or cardiovascular disease."

Does this make fruits and vegetables bad? No, of course not. But is does make them much less of an invisible cloak of protection against cancer and disease than they are often portrayed as being, and certainly not a life essential to be foisted on kids at government expense.

The definition of insanity is to continue to do the same thing you've been doing all along and expect a different result.