This code system http://terminology.hl7.org/CodeSystem/goal-priority defines the following codes:

Code	Display	Definition
high-priority	High Priority	Indicates that the goal is of considerable importance and should be a primary focus of care delivery.
medium-priority	Medium Priority	Indicates that the goal has a reasonable degree of importance and that concrete action should be taken towards the goal. Attainment is not as critical as high-priority goals.
low-priority	Low Priority	The goal is desirable but is not sufficiently important to devote significant resources to. Achievement of the goal may be sought when incidental to achieving other goals.