• Include these codes as defined in http://terminology.hl7.org/CodeSystem/v3-ObservationValue version 2.1.0

  Code	Display	Definition
  DS	daytime shift	A person who is scheduled for work during daytime hours (for example between 6am and 6pm) on a regular basis.
  EMS	early morning shift	Consistent Early morning schedule of 13 hours or less per shift (between 2 am and 2 pm)
  ES	evening shift	A person who is scheduled for work during evening hours (for example between 2pm and midnight) on a regular basis.
  NS	night shift	Scheduled for work during nighttime hours (for example between 9pm and 8am) on a regular basis.
  RSWN	rotating shift with nights	Scheduled for work times that change periodically between days, and/or evenings, and includes some night shifts.
  RSWON	rotating shift without nights	Scheduled for work days/times that change periodically between days, but does not include night or evening work.
  SS	split shift	Shift consisting of two distinct work periods each day that are separated by a break of a few hours (for example 2 to 4 hours)
  VLS	very long shift	Shifts of 17 or more hours.
  VS	variable shift	Irregular, unpredictable hours scheduled on a short notice (for example, less than 2 day notice): inconsistent schedule, on-call, as needed, as available.

This value set expansion contains 9 concepts.