Doctor

Doctor is a possible secondary Skill you can level up during gameplay.

It's starting value is: $30+1*Perception+3*Intelligence+1*Agility+1*Luck$

Being a secondary skill, it can be leveled up to 200%.

Each % after 100% increases the amount of bleeding you heal with Doctor by 1. Up to 100%, you will always heal 0 Bleed with a normal usage of the Doctor Skill on an unbandaged target. At 200%, you will heal 100 Bleed.
A higher Skill, also decreases the amount of Action Points the Doctor Skill uses up. Up to 100%, you will always use up 200 Action Points to use the Doctor Skill, with each 1% afterwards decreasing it by 1 AP, down to 100 Action Points at 200%.
The Perk Dr. Strangelove can further increase this value by 50 Health Points, as well as using specific Doctor Items.

The formula on how much you heal is as follows: $0+\max((skill-100),0)+Dr.Strangelove(50)$

The formula on how much AP you use up is: $(200-FieldMedic(25))*(200-\max((skill-100),0))$

After 100%, you unlock item perks for Doctor items, every 25%. This means you get your first item perk unlocked at 100%, then at 125%, 150%, 175%, with the last one unlocking at 200% - making it quite beneficial to get it all the way up to 200%, if you are using Doctor items.