Healing

First Aid:

Do a medicine check against the hardest difficulty of the SPECIALs you are trying to heal:

End dc 12
Str/agi dc 15
Cha/per dc 18
Int dc 21

Yes and – 1,5*target base endurance + your medicine skill lvl (not total)
Yes – target base endurance + your medicine skill lvl (not total)
Yes but – 0,5*target base endurance + your medicine skill lvl (not total)

Stats at 0 or 1 can max be healed to half of maximum (round down).
Else up to one less than max.

Long term care
When resting a day and having medical care, the doctor may make an additional first aid check, but targeting a specific SPECIAL, but not healing additional from targets endurance.

Natural healing
If resting a full day, you regain 1 lost SPECIAL
In the following order:

Endurance, Strength or Agility, Perception, Intelligence.
Charisma needs cosmetics surgery.

Healing

Fallout: Suburbia doktor_fritz