Question about + skill damage

Okay I have a quick question about "+ skill damage"
Does "+ skill damage" effect "on striking/on attack/when struck" skills?

Example: Does - (

Trang-Oul's Claws: +25% poison damage) - effect - (

Andariel's Visage: level 15

Poison Nova when struck)?

I would love to know
Thx in advance

Logic tells me it should work just like how synergies apply to chance to cast/striking/etc. A quick google search didn't come up with anything relevant, so you could test it yourself on 0% PR trash with decent hp (e.g.

Wendigo in

Den of Evil).

judging by 10 and 20 year old posts, yes

https://www.purediablo.com/forumarchive ... rk.293165/

https://forums.d2jsp.org/topic.php?t=60862573