Age is an indicator of exposure to the subject matter you seek to proliferate, I guess, coupled with your formal education and other qualifications. I think there is not necessarily a relationship without direct definition of what exactly is this creativity? Is the creativity of an artist the same as, say, a scientist? Would someone working on a canvas be, in definition, in the same position as someone working on a quantitative definition in, say, physics? I do not think so. Consider adding in a sample pool and then defining them, compare a specific vocation perhaps.
I think context is important. Simplification of these ideas, such as direct application across such a large sample pool, without categorization of this pool is the wrong approach.
In short, I'd say, there is no link based on the nature of question...
I do not think that there is a direct or inverse proportionality between age & creativity according to what I have witnessed among relatives, friends, and neighbors. It is a case by case scenery in which you will see two classmates (same age) with one of them ascending in creativity while the other is descending as time goes by.
Certainly there is a need to carry out an investigation, with scientific parameters to reach the results. In particular, I think that accumulated experience must also be one of the variables involved. Greetings!
There is no relation. The secret to creativity is with having an innovative mind, being curious to finding ways of solving mankind's problems in simple, easier and less costly fashion. My 5 year old son who loves to create yesterday created a beautiful aeroplane paper origami which some Graphic design students of average age 17 years couldn't do.
I have search and have not come across any scientific evident that state whether there is a positive or negative correlation been Age and Creativity. Age comes with experience and comes with exploration. Experience can affect your exploratory abilities. However, irrespective of you age you can still be creativity as illustrated by Brother Dickson.