Prestige Class PvP contributions can be broken down into five roles. Scores assigned to the classes represent their best potential.
The ability to effectively output high health loss via spells and weapon attacks. This category can be broken down into Burst, which can be difficult to anticipate, and Sustained, which is more reliable but can be negated by healers more easily. Characters with high Damage scores are often the most numerous members of a PvP group.
The capacity to disrupt, disable, restrain or immobilize foes. Characters with high Control scores can protect their allies with disruptive effects and prime enemies for defeat with properly timed disables.
The ability to diminish foes, empower allies and employ key non-combat oriented powers. Characters with high Utility scores may empower allies with buffs, dispel harmful hexes, weaken foes with debuffs or summon allies from distant lands to their side.
The restoration hit points that have been lost in battle. This includes topping off characters who take chip damage as well as swiftly sustaining life on an ally who has been focused on. Characters with high Healing scores can cast powers on themselves or allies which immediately restore great amounts of health or mend wounds over time.
Survival includes all manner self-preservation tactics. Characters with high Survival scores might be particularly elusive, wear protective armor, possess hardy constitutions or employ invisibility.