define "Initial Population":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) in Interval[18, 75]

define "Patient Age Less than 18 Years Start of Measurement Period":
  AgeInYearsAt(date from start of "Measurement Period") < 18

define "Patient Age 18 Years or Older at Start of Measurement Period":
  AgeInYearsAt(date from start of "Measurement Period") >= 18

define "Initial Population2":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) in Interval[19, 76]

define "SDE Sex":
  case
      when Patient.gender = 'male' then Code { code: 'M', system: 'http://hl7.org/fhir/v3/AdministrativeGender', display: 'Male' }
      when Patient.gender = 'female' then Code { code: 'F', system: 'http://hl7.org/fhir/v3/AdministrativeGender', display: 'Female' }
      else null
    end

define "SDE Payer":
  [Coverage: type in "Payer Type"] Payer
    return {
      code: Payer.type,
      period: Payer.period
    }

define "SDE Ethnicity":
  Patient.ethnicity E
    return Tuple {
      codes: { E.ombCategory } union E.detailed,
      display: E.text
    }

define "SDE Race":
  Patient.race R
    return Tuple {
      codes: R.ombCategory union R.detailed,
      display: R.text
    }

define "SDE Sex":
  SDE."SDE Sex"

define "RAV Patient Too Old at Start of Measurement Period":
  AgeInYearsAt(date from start of "Measurement Period") > 80

define "RAV Patient Too Young at Start of Measurement Period":
  AgeInYearsAt(date from start of "Measurement Period") < 5

define "Patient Age Less than 18 Years Start of Measurement Period":
  AgeInYearsAt(date from start of "Measurement Period") < 18

define "SDE Payer":
  SDE."SDE Payer"

define "Initial Population":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) in Interval[18, 75]

define "SDE Ethnicity":
  SDE."SDE Ethnicity"

define "Patient Age 18 Years or Older at Start of Measurement Period":
  AgeInYearsAt(date from start of "Measurement Period") >= 18

define "Initial Population2":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) in Interval[19, 76]

define "SDE Race":
  SDE."SDE Race"

define function ToInterval(period FHIR.Period):
    if period is null then
        null
    else
        if period."start" is null then
            Interval(period."start".value, period."end".value]
        else
            Interval[period."start".value, period."end".value]

define function ToString(value uri): value.value

define function ToCode(coding FHIR.Coding):
    if coding is null then
        null
    else
        System.Code {
          code: coding.code.value,
          system: coding.system.value,
          version: coding.version.value,
          display: coding.display.value
        }