Habit formation

Read here http://economistsview.typepad.com/economistsview/2008/07/habit-formation.html

Someone decided to use marketing strategies to convince people to use soap, and claims:

"By last year, Ghanaians surveyed by members of Dr. Curtis’s team reported a 13 percent increase in the use of soap after the toilet. Another measure showed even greater impact: reported soap use before eating went up 41 percent."

First off, how do you calculate these statistics? I'm dying to know. If the campaign was successful in creating disgust, it could very easily lead people to over report (if they were being surveyed) the amount of soap they were using. If this is coupled with the fact that in fact behaviour did not change (or changed very little) then these statistics are more than over-statement, they are signifying behaviour that isn't happening.

Second, there is the usual confusion between the treatment and the cause. How much of the increase reported is due to the advertising campaign? And how much of the effect is due to a combination of traditional + advert campaign?

I have to say I have no problems in using marketing experts to sell hygiene. There are some idiots at the website given above that have problems like that.