Does anyone know an easy way to detect whether the player just used a shout? I want to make it so that shouting improves your Speech skill and while I could attach a script to every magic effect used for shouts, I'd rather use a generic solution.

From searching the CS wiki I came across http://www.creationkit.com/OnSpellCast_-_ObjectReference, which seem to be my best bet, but I'm not sure if shouts count as spells. And even if they do i'm unsure how to identify that the spell cast was a shout.

I know it should be possible, because there is that one radiant quest where you shout in a town and you get a letter about a word wall. However, I couldn't find anything useful while examining the related scripts.