http://wiki.ffxiclopedia.org/wiki/Damage
Then scroll down to equipment list. Remember this is Damage Taken +% and not Physical Damage Taken -%
Also read comments others made here:
http://www.ffxiah.com/item/17113/owleyes
Gear pieces that
reduce damage would have listed it as "Physical Damage Taken -%" oppose to Damage Taken +%. Evidence can be seen in Colonization Reives when Yellow Message pops up
"Damage Taken" where people receive an extra bonus of Bayld for tanking.
To further support my statement check out the Black Mage Valkyrie set.
http://wiki.ffxiclopedia.org/wiki/Valkyrie's_Coat_Set
This is the HQ set of Shadow Coat Set. The Shadow Coat Set is a mage cloth set providing significant bonuses to Magic Accuracy and enmity reduction. It also provides smaller bonuses to MP, Magic Attack Bonus, and various caster stats.
As a drawback, extra damage is taken while this set is equipped, in even greater quantity than the NQ version. The set is attainable through abjurations obtained from Einherjar.
Although some pieces state Physical Damage Taken +%
Valkyrie Trews has
Damage Taken +5%.
Valkyrie's trews
[Legs] All Races
DEF: 29
"Magic Atk. Bonus" +5
Magic Accuracy +5 Enmity -3
Damage taken +5%
Lv. 75 WHM / BLM / RDM / BRD / SMN
Hope this answers your question.