For every class there are between 4 to 5 relevant statistics that govern their performance in Dark Age of Camelot.
Strength governs damage output for many melee weapons and is evident in the weaponskill factor shown on the character page.
Constitution has a direct correlation to your hitpoints as a bonus to the hit point progression table of your class.
Dexterity factors into some weaponskill calculations, notable all ranged attacks and it factors in to many defenses like shield blocking, parry, evade and it factors into the speed of spellcasting.
Quickness modifies all melee combat rate of swings and the chance to evade in combat.
The remaining stats are Piety, Charisma, Empathy, Intelligence. One of these stats may affect your character such as piety being the power pool and damage modifier for midgard casters while charisma affects skald performance.
In all cases the general effects of increasing stats are 1% modification for every 10 points above 50 until 250, then 1% for every 20 points from 251 – 350, at which all stats are hard capped.