It turns out that the length of time spent living abroad is a significant predictor of coming up with the most creative solution. But, it was only living abroad that rewarded students with increased creativity. Two weeks of hostel hopping don’t count.
The article is gated, but you can read the abstract here.
I don't doubt that living abroad enhances creativity somewhat, but I wish they would show some numbers. A "significant" difference does not imply a considerable difference. I want to know the size of the effect, and how it compares to other factors.