There is a great amount of variation in the results of IQ tests. Firstly, a person can score different each time they take it, based on their surroundings and mindset. And some tests may just be slightly skewed toward a particular person's world view. Also, even if the IQ consistently say your friend's IQ is higher, that doesn't mean they are smarter. It only means their IQ is greater. There are many different kinds of intelligence that are not measured by an IQ test, such as emotional intelligence, social intelligence, and kinesthetic intelligence.