define "Initial Population":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) >= 65
    and exists "Qualifying Encounters"

define "Denominator":
  "Initial Population"

define "Denominator Exclusions":
  Hospice."Has Hospice Services"
    or PalliativeCare."Has Palliative Care in the Measurement Period"

define "Numerator 1":
  exists "Same High Risk Medications Ordered on Different Days"
    or "Two High Risk Medications with Prolonged Duration"
    or "High Risk Medications with Average Daily Dose Criteria"

define "Initial Population":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) >= 65
    and exists "Qualifying Encounters"

define "Denominator":
  "Initial Population"

define "Denominator Exclusions":
  Hospice."Has Hospice Services"
    or PalliativeCare."Has Palliative Care in the Measurement Period"

define "Numerator 2":
  ( "More than One Antipsychotic Order"
      and ( not exists ( ( "Schizophrenia Diagnosis"
            union "Bipolar Disorder Diagnosis" ) AntipsychoticTreatedDiagnoses
            where AntipsychoticTreatedDiagnoses.prevalenceInterval ( ) overlaps Interval[start of "Measurement Period" - 1 year, "Antipsychotic Index Prescription Start Date"]
        )
      )
  )
    or ( "More than One Benzodiazepine Order"
        and ( not exists ( ( "Seizure Disorder Diagnosis"
              union "REM Sleep Behavior Disorder Diagnosis"
              union "Benzodiazepine Withdrawal Diagnosis"
              union "Alcohol Withdrawal Diagnosis"
              union "Generalized Anxiety Disorder Diagnosis" ) BenzodiazepineTreatedDiagnoses
              where BenzodiazepineTreatedDiagnoses.prevalenceInterval ( ) overlaps Interval[start of "Measurement Period" - 1 year, "Benzodiazepine Index Prescription Start Date"]
          )
        )
    )

define "Initial Population":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) >= 65
    and exists "Qualifying Encounters"

define "Denominator":
  "Initial Population"

define "Denominator Exclusions":
  Hospice."Has Hospice Services"
    or PalliativeCare."Has Palliative Care in the Measurement Period"

define "Numerator 3":
  "Numerator 2"
    or ( "Numerator 1"
        and not "Numerator 2"
    )

define "Has Hospice Services":
  exists ((([Encounter: "Encounter Inpatient"]).isEncounterPerformed()) InpatientEncounter
      where (InpatientEncounter.hospitalization.dischargeDisposition ~ "Discharge to home for hospice care (procedure)"
          or InpatientEncounter.hospitalization.dischargeDisposition ~ "Discharge to healthcare facility for hospice care (procedure)"
      )
        and InpatientEncounter.period ends during day of "Measurement Period"
  )
    or exists ((([Encounter: "Hospice Encounter"]).isEncounterPerformed()) HospiceEncounter
        where HospiceEncounter.period overlaps day of "Measurement Period"
    )
    or exists ((([ObservationScreeningAssessment: "Hospice care [Minimum Data Set]"]).isAssessmentPerformed()) HospiceAssessment
        where HospiceAssessment.value ~ "Yes (qualifier value)"
          and HospiceAssessment.effective.toInterval() overlaps day of "Measurement Period"
    )
    or exists ((([ServiceRequest: "Hospice Care Ambulatory"]).isInterventionOrder()) HospiceOrder
        where HospiceOrder.authoredOn during day of "Measurement Period"
    )
    or exists ((([Procedure: "Hospice Care Ambulatory"]).isInterventionPerformed()) HospicePerformed
        where HospicePerformed.performed.toInterval() overlaps day of "Measurement Period"
    )
    or exists ((([ConditionProblemsHealthConcerns: "Hospice Diagnosis"]
        union [ConditionEncounterDiagnosis: "Hospice Diagnosis"]).verified()) HospiceCareDiagnosis
        where HospiceCareDiagnosis.prevalenceInterval() overlaps day of "Measurement Period"
    )

define "Has Palliative Care in the Measurement Period":
  exists ((([ObservationScreeningAssessment: "Functional Assessment of Chronic Illness Therapy - Palliative Care Questionnaire (FACIT-Pal)"]).isAssessmentPerformed()) PalliativeAssessment
      where PalliativeAssessment.effective.toInterval() overlaps day of "Measurement Period"
  )
    or exists ((([ConditionProblemsHealthConcerns: "Palliative Care Diagnosis"]
    union [ConditionEncounterDiagnosis: "Palliative Care Diagnosis"]).verified()) PalliativeDiagnosis
        where PalliativeDiagnosis.prevalenceInterval() overlaps day of "Measurement Period"
    )
    or exists ((([Encounter: "Palliative Care Encounter"]).isEncounterPerformed()) PalliativeEncounter
        where PalliativeEncounter.period overlaps day of "Measurement Period"
    )
    or exists ((([Procedure: "Palliative Care Intervention"]).isInterventionPerformed()) PalliativeIntervention
        where PalliativeIntervention.performed.toInterval() overlaps day of "Measurement Period"
    )

define "SDE Sex":
  case
    when Patient.sex = '248153007' then "Male (finding)"
    when Patient.sex = '248152002' then "Female (finding)"
    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 fluent function medicationRequestPeriod(Request "MedicationRequest"):
  Request R
    let
      dosage: singleton from R.dosageInstruction,
      doseAndRate: singleton from dosage.doseAndRate,
      timing: dosage.timing,
      frequency: Coalesce(timing.repeat.frequencyMax, timing.repeat.frequency),
      period: Quantity(timing.repeat.period, timing.repeat.periodUnit),
      doseRange: doseAndRate.dose,
      doseQuantity: doseAndRate.dose,
      dose: Coalesce(end of doseRange, doseQuantity),
      dosesPerDay: Coalesce(ToDaily(frequency, period), Count(timing.repeat.timeOfDay), 1.0),
      boundsPeriod: timing.repeat.bounds as Interval<DateTime>,
      daysSupply: (convert R.dispenseRequest.expectedSupplyDuration to days).value,
      quantity: R.dispenseRequest.quantity,
      refills: Coalesce(R.dispenseRequest.numberOfRepeatsAllowed, 0),
      startDate:
        Coalesce(
          date from start of boundsPeriod,
          date from R.authoredOn,
          date from start of R.dispenseRequest.validityPeriod
        ),
      totalDaysSupplied: Coalesce(daysSupply, quantity.value / (dose.value * dosesPerDay)) * (1 + refills)
    return
      if startDate is not null and totalDaysSupplied is not null then
        Interval[startDate, startDate + Quantity(totalDaysSupplied - 1, 'day') ]
      else if startDate is not null and boundsPeriod."high" is not null then
        Interval[startDate, date from end of boundsPeriod]
      else
        null

/**********************************************************************/
/* Functions in this region are copied from opioid-mme-r4             */
/**********************************************************************/

define function Quantity(value Decimal, unit String):
  if value is not null then
    System.Quantity { value: value, unit: unit }
  else
    null

/*
 Goal is to get to number of days
 Two broad approaches to the calculation:
  1) Based on supply and frequency, calculate the number of expected days the medication will cover/has covered
  2) Based on relevant period, determine a covered interval and calculate the length of that interval in days
This topic covers several use cases and illustrates how to calculate Cumulative
Medication Duration for each type of medication resource using the supply and
frequency approach.
*/

/*
  For the first approach, we need to get from frequency to a frequency/day
  So we define ToDaily
*/

/*
  Calculates daily frequency given frequency within a period
*/
define function ToDaily(frequency System.Integer, period System.Quantity):
  case period.unit
    when 'h' then frequency * (24.0 / period.value)
    when 'min' then frequency * (24.0 / period.value) * 60
    when 's' then frequency * (24.0 / period.value) * 60 * 60
    when 'd' then frequency * (24.0 / period.value) / 24
    when 'wk' then frequency * (24.0 / period.value) / (24 * 7)
    when 'mo' then frequency * (24.0 / period.value) / (24 * 30) /* assuming 30 days in month */
    when 'a' then frequency * (24.0 / period.value) / (24 * 365) /* assuming 365 days in year */
    when 'hour' then frequency * (24.0 / period.value)
    when 'minute' then frequency * (24.0 / period.value) * 60
    when 'second' then frequency * (24.0 / period.value) * 60 * 60
    when 'day' then frequency * (24.0 / period.value) / 24
    when 'week' then frequency * (24.0 / period.value) / (24 * 7)
    when 'month' then frequency * (24.0 / period.value) / (24 * 30) /* assuming 30 days in month */
    when 'year' then frequency * (24.0 / period.value) / (24 * 365) /* assuming 365 days in year */
    when 'hours' then frequency * (24.0 / period.value)
    when 'minutes' then frequency * (24.0 / period.value) * 60
    when 'seconds' then frequency * (24.0 / period.value) * 60 * 60
    when 'days' then frequency * (24.0 / period.value) / 24
    when 'weeks' then frequency * (24.0 / period.value) / (24 * 7)
    when 'months' then frequency * (24.0 / period.value) / (24 * 30) /* assuming 30 days in month */
    when 'years' then frequency * (24.0 / period.value) / (24 * 365) /* assuming 365 days in year */
    else Message(null, true, 'CMDLogic.ToDaily.UnknownUnit', ErrorLevel, 'Unknown unit ' & period.unit)
  end

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

define "More than One Antipsychotic Order":
  exists ( [MedicationRequest: "Potentially Harmful Antipsychotics for Older Adults"] ).moreThanOneOrder ( )

define "Schizophrenia Diagnosis":
  ( [ConditionProblemsHealthConcerns: "Schizophrenia"]
      union [ConditionEncounterDiagnosis: "Schizophrenia"]
  ).verified ( )

define "Bipolar Disorder Diagnosis":
  ( [ConditionProblemsHealthConcerns: "Bipolar Disorder"]
      union [ConditionEncounterDiagnosis: "Bipolar Disorder"]
  ).verified ( )

define "Antipsychotic Index Prescription Start Date":
  First((([MedicationRequest: "Potentially Harmful Antipsychotics for Older Adults"]).isMedicationOrder()) AntipsychoticMedication
      where AntipsychoticMedication.authoredOn during "Measurement Period"
      return AntipsychoticMedication.authoredOn
      sort asc
  )

define "More than One Benzodiazepine Order":
  exists ( [MedicationRequest: "Potentially Harmful Benzodiazepines for Older Adults"] ).moreThanOneOrder ( )

define "Seizure Disorder Diagnosis":
  ( [ConditionProblemsHealthConcerns: "Seizure Disorder"]
      union [ConditionEncounterDiagnosis: "Seizure Disorder"]
  ).verified ( )

define "REM Sleep Behavior Disorder Diagnosis":
  ( [ConditionProblemsHealthConcerns: "REM Sleep Behavior Disorder"]
      union [ConditionEncounterDiagnosis: "REM Sleep Behavior Disorder"]
  ).verified ( )

define "Benzodiazepine Withdrawal Diagnosis":
  ( [ConditionProblemsHealthConcerns: "Benzodiazepine Withdrawal"]
      union [ConditionEncounterDiagnosis: "Benzodiazepine Withdrawal"]
  ).verified ( )

define "Alcohol Withdrawal Diagnosis":
  ( [ConditionProblemsHealthConcerns: "Alcohol Withdrawal"]
      union [ConditionEncounterDiagnosis: "Alcohol Withdrawal"]
  ).verified ( )

define "Generalized Anxiety Disorder Diagnosis":
  ( [ConditionProblemsHealthConcerns: "Generalized Anxiety Disorder"]
      union [ConditionEncounterDiagnosis: "Generalized Anxiety Disorder"]
  ).verified ( )

define "Benzodiazepine Index Prescription Start Date":
  First((([MedicationRequest: "Potentially Harmful Benzodiazepines for Older Adults"]).isMedicationOrder()) BenzodiazepineMedication
      where BenzodiazepineMedication.authoredOn during "Measurement Period"
      return BenzodiazepineMedication.authoredOn
      sort asc
  )

define "Numerator 2":
  ( "More than One Antipsychotic Order"
      and ( not exists ( ( "Schizophrenia Diagnosis"
            union "Bipolar Disorder Diagnosis" ) AntipsychoticTreatedDiagnoses
            where AntipsychoticTreatedDiagnoses.prevalenceInterval ( ) overlaps Interval[start of "Measurement Period" - 1 year, "Antipsychotic Index Prescription Start Date"]
        )
      )
  )
    or ( "More than One Benzodiazepine Order"
        and ( not exists ( ( "Seizure Disorder Diagnosis"
              union "REM Sleep Behavior Disorder Diagnosis"
              union "Benzodiazepine Withdrawal Diagnosis"
              union "Alcohol Withdrawal Diagnosis"
              union "Generalized Anxiety Disorder Diagnosis" ) BenzodiazepineTreatedDiagnoses
              where BenzodiazepineTreatedDiagnoses.prevalenceInterval ( ) overlaps Interval[start of "Measurement Period" - 1 year, "Benzodiazepine Index Prescription Start Date"]
          )
        )
    )

define "Same High Risk Medications Ordered on Different Days":
  ( [MedicationRequest: "Potentially Harmful Antihistamines for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Antiparkinsonian Agents for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Gastrointestinal Antispasmodics for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Dipyridamole Medications"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Guanfacine Medications"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Nifedipine Medications"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Antidepressants for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Barbiturates for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "ergoloid mesylates, USP 1 MG Oral Tablet"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Meprobamate Medications"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Estrogens for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Sulfonylureas for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Desiccated Thyroid Medications"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Nonbenzodiazepine Hypnotics for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Skeletal Muscle Relaxants for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Potentially Harmful Pain Medications for Older Adults"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Megestrol Medications"] ).moreThanOneOrder ( )
    union ( [MedicationRequest: "Meperidine Medications"] ).moreThanOneOrder ( )

define "Two High Risk Medications with Prolonged Duration":
  Sum((([MedicationRequest: "Potentially Harmful Antiinfectives for Older Adults"]).moreThanOneOrder()) AntiInfectives
      let DaysSupply: AntiInfectives.medicationRequestPeriodInDays()
      return all DaysSupply
  ) > 90

define "High Risk Medications with Average Daily Dose Criteria":
  exists ( ( [MedicationRequest: "Digoxin Medications"] DigoxinOrdered
        where DigoxinOrdered.averageDailyDose ( ) > 0.125 'mg/d'
    ).moreThanOneOrder ( )
  )
    or exists ( ( [MedicationRequest: "Doxepin Medications"] DoxepinOrdered
          where DoxepinOrdered.averageDailyDose ( ) > 6 'mg/d'
      ).moreThanOneOrder ( )
    )

define "Numerator 1":
  exists "Same High Risk Medications Ordered on Different Days"
    or "Two High Risk Medications with Prolonged Duration"
    or "High Risk Medications with Average Daily Dose Criteria"

define "Numerator 3":
  "Numerator 2"
    or ( "Numerator 1"
        and not "Numerator 2"
    )

define "Qualifying Encounters":
  ( ( [Encounter: "Office Visit"]
      union [Encounter: "Ophthalmological Services"]
      union [Encounter: "Preventive Care Services Established Office Visit, 18 and Up"]
      union [Encounter: "Discharge Services Nursing Facility"]
      union [Encounter: "Nursing Facility Visit"]
      union [Encounter: "Care Services in Long Term Residential Facility"]
      union [Encounter: "Preventive Care Services Initial Office Visit, 18 and Up"]
      union [Encounter: "Annual Wellness Visit"]
      union [Encounter: "Home Healthcare Services"]
      union [Encounter: "Telephone Visits"]
      union [Encounter: "Virtual Encounter"]
      union ( [Encounter] E
          where exists ( ( E.type ) T
              where T ~ "Office or other outpatient visit for the evaluation and management of an established patient that may not require the presence of a physician or other qualified health care professional"
          )
      )
  ).isEncounterPerformed ( ) ) ValidEncounters
    where ValidEncounters.period during "Measurement Period"

define "Initial Population":
  AgeInYearsAt(date from 
    end of "Measurement Period"
  ) >= 65
    and exists "Qualifying Encounters"

define "Denominator":
  "Initial Population"

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

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

define "Denominator Exclusions":
  Hospice."Has Hospice Services"
    or PalliativeCare."Has Palliative Care in the Measurement Period"

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

define fluent function moreThanOneOrder(Medication List<MedicationRequest>):
  ( Medication.isMedicationOrder ( ) ) OrderMedication1
    with ( Medication.isMedicationOrder ( ) ) OrderMedication2
      such that ( OrderMedication1.authoredOn during "Measurement Period"
          and OrderMedication1.dispenseRequest.numberOfRepeatsAllowed >= 1
      )
        or ( date from OrderMedication1.authoredOn !~ date from OrderMedication2.authoredOn
            and OrderMedication1.authoredOn during "Measurement Period"
            and OrderMedication2.authoredOn during "Measurement Period"
        )
        or ( date from OrderMedication1.authoredOn ~ date from OrderMedication2.authoredOn
            and OrderMedication1.authoredOn during "Measurement Period"
            and date from start of OrderMedication1.medicationRequestPeriod ( ) !~ date from start of OrderMedication2.medicationRequestPeriod ( )
            and start of OrderMedication1.medicationRequestPeriod ( ) during "Measurement Period"
            and start of OrderMedication2.medicationRequestPeriod ( ) during "Measurement Period"
        )
    return OrderMedication1

define fluent function medicationRequestPeriodInDays(Request MedicationRequest):
  Request R
    let dosage: singleton from R.dosageInstruction,
    doseAndRate: singleton from dosage.doseAndRate,
    timing: dosage.timing,
    frequency: Coalesce(timing.repeat.frequencyMax, timing.repeat.frequency),
    period: CMD."Quantity" ( timing.repeat.period, timing.repeat.periodUnit ),
    doseRange: doseAndRate.dose,
    doseQuantity: doseAndRate.dose,
    dose: Coalesce(
      end of doseRange, doseQuantity
    ),
    dosesPerDay: Coalesce((CMD."ToDaily"(frequency, period)), Count(timing.repeat.timeOfDay), 1.0),
    boundsPeriod: timing.repeat.bounds as Interval<DateTime>,
    daysSupply: ( convert R.dispenseRequest.expectedSupplyDuration to days ).value,
    quantity: R.dispenseRequest.quantity,
    refills: Coalesce(R.dispenseRequest.numberOfRepeatsAllowed, 0),
    startDate: Coalesce(date from start of boundsPeriod, date from R.authoredOn, date from start of R.dispenseRequest.validityPeriod),
    totalDaysSupplied: Coalesce(daysSupply, quantity.value /(dose.value * dosesPerDay)) * ( 1 + refills )
    return totalDaysSupplied

define fluent function averageDailyDose(MedicationRequest MedicationRequest):
  MedicationRequest Order
    let MedicationStrength: Order.getMedicationCode ( ).medicationStrengthPerUnit ( ),
    DaysSupplied: Order.medicationRequestPeriodInDays ( )
    return if DaysSupplied is not null
      and ( MedicationStrength.unit = 'mg'
          or ( MedicationStrength.unit = 'mg/mL'
              and Order.dispenseRequest.quantity.unit = 'mL'
          )
      ) then ( ( Order.dispenseRequest.quantity * MedicationStrength ) / Quantity { value: DaysSupplied, unit: 'd' } ) 
      else null

define fluent function medicationStrengthPerUnit(Strength Concept):
  case
    when Strength ~ "digoxin 0.05 MG/ML Oral Solution" then 0.05 'mg/mL'
    when Strength ~ "digoxin 0.0625 MG Oral Tablet" then 0.0625 'mg'
    when Strength ~ "1 ML digoxin 0.1 MG/ML Injection" then 0.1 'mg/mL'
    when Strength ~ "digoxin 0.125 MG Oral Tablet" then 0.125 'mg'
    when Strength ~ "digoxin 0.25 MG Oral Tablet" then 0.25 'mg'
    when Strength ~ "2 ML digoxin 0.25 MG/ML Injection" then 0.25 'mg/mL'
    when Strength ~ "doxepin 3 MG Oral Tablet" then 3 'mg'
    when Strength ~ "doxepin 6 MG Oral Tablet" then 6 'mg'
    when Strength ~ "doxepin 10 MG Oral Capsule" then 10 'mg'
    when Strength ~ "doxepin 10 MG/ML Oral Solution" then 10 'mg/mL'
    when Strength ~ "doxepin 25 MG Oral Capsule" then 25 'mg'
    when Strength ~ "doxepin 50 MG Oral Capsule" then 50 'mg'
    when Strength ~ "doxepin 75 MG Oral Capsule" then 75 'mg'
    when Strength ~ "doxepin 100 MG Oral Capsule" then 100 'mg'
    when Strength ~ "doxepin 150 MG Oral Capsule" then 150 'mg' 
    else null end

/*
@description: Returns the medication code for the given MedicationRequest
*/
define fluent function getMedicationCode(request MedicationRequest):
  if request.medication is Concept then
  	  request.medication as Concept
  	else
  	  (singleton from ([Medication] M where request.medication.references(M))).code

define function ToString(value uri): value.value

/*
@description: Converts the given [Period](https://hl7.org/fhir/datatypes.html#Period)
value to a CQL DateTime Interval
@comment: If the start value of the given period is unspecified, the starting
boundary of the resulting interval will be open (meaning the start of the interval
is unknown, as opposed to interpreted as the beginning of time).
*/
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]

/*
@description: Converts the given FHIR [CodeableConcept](https://hl7.org/fhir/datatypes.html#CodeableConcept) value to a CQL Concept.
*/
define function ToConcept(concept FHIR.CodeableConcept):
    if concept is null then
        null
    else
        System.Concept {
            codes: concept.coding C return ToCode(C),
            display: concept.text.value
        }

/*
@description: Converts the given FHIR [Coding](https://hl7.org/fhir/datatypes.html#Coding) value to a CQL Code.
*/
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
        }

//Medication, Order
define fluent function isMedicationOrder(MedicationRequest List<MedicationRequest>):
  MedicationRequest M
    where M.status in { 'active', 'completed' }
    and M.intent in {'order', 'original-order', 'reflex-order', 'filler-order', 'instance-order'}

//This library contains functions used to constrain FHIR resource elements for measures authored by NCQA, based on QICore 6.0.0 resources including IG and authoring patterns. The functions may appear similar to some QICoreCommon functions but differ in that they have constraints that are relevant for measures authored by NCQA.

//Condition
//Returns conditions in the given list that either have no verification status or have a verification status of confirmed, unconfirmed, provisional, or differential
define fluent function verified(conditions List<Choice<ConditionProblemsHealthConcerns, ConditionEncounterDiagnosis>>):
  conditions C
    where C.verificationStatus is not null implies
      (C.verificationStatus ~ "confirmed"
        or C.verificationStatus ~ "unconfirmed"
        or C.verificationStatus ~ "provisional"
        or C.verificationStatus ~ "differential"
      )

//Encounter, Performed
//General usage unless required otherwise by measure intent (e.g., follow-up encounters)
define fluent function isEncounterPerformed(Enc List<Encounter>):
  Enc E
    where E.status = 'finished'

//Assessment, Performed
define fluent function isAssessmentPerformed(Obs List<ObservationScreeningAssessment>):
  Obs O
    where O.status in { 'final', 'amended', 'corrected' }

//Intervention, Order
define fluent function isInterventionOrder(ServiceRequest List<ServiceRequest>):
  ServiceRequest S
    where S.status in { 'active', 'completed' }
      and S.intent in {'order', 'original-order', 'reflex-order', 'filler-order', 'instance-order'}

//Intervention, Performed
define fluent function isInterventionPerformed(Proc List<Procedure>):
  Proc P
    where P.status ~ 'completed'

/*
@description: Returns true if the given reference is to the given resource
@comment: Returns true if the `id` element of the given resource exactly equals the tail of the given reference.
NOTE: This function assumes resources from the same source server.
*/
define fluent function references(reference Reference, resource Resource):
  resource.id = Last(Split(reference.reference, '/'))

/*
@description: Normalizes a value that is a choice of timing-valued types to an equivalent interval
@comment: Normalizes a choice type of DateTime, Quanitty, Interval<DateTime>, or Interval<Quantity> types
to an equivalent interval. This selection of choice types is a superset of the majority of choice types that are used as possible
representations for timing-valued elements in QICore, allowing this function to be used across any resource.
The input can be provided as a DateTime, Quantity, Interval<DateTime> or Interval<Quantity>.
The intent of this function is to provide a clear and concise mechanism to treat single
elements that have multiple possible representations as intervals so that logic doesn't have to account
for the variability. More complex calculations (such as medication request period or dispense period
calculation) need specific guidance and consideration. That guidance may make use of this function, but
the focus of this function is on single element calculations where the semantics are unambiguous.
If the input is a DateTime, the result a DateTime Interval beginning and ending on that DateTime.
If the input is a Quantity, the quantity is expected to be a calendar-duration interpreted as an Age,
and the result is a DateTime Interval beginning on the Date the patient turned that age and ending immediately before one year later.
If the input is a DateTime Interval, the result is the input.
If the input is a Quantity Interval, the quantities are expected to be calendar-durations interpreted as an Age, and the result
is a DateTime Interval beginning on the date the patient turned the age given as the start of the quantity interval, and ending
immediately before one year later than the date the patient turned the age given as the end of the quantity interval.
If the input is a Timing, an error will be thrown indicating that Timing calculations are not implemented. Any other input will reslt in a null DateTime Interval
*/
define fluent function toInterval(choice Choice<DateTime, Quantity, Interval<DateTime>, Interval<Quantity>, Timing>):
  case
	  when choice is DateTime then
    	Interval[choice as DateTime, choice as DateTime]
		when choice is Interval<DateTime> then
  		choice as Interval<DateTime>
		when choice is Quantity then
		  Interval[Patient.birthDate + (choice as Quantity),
			  Patient.birthDate + (choice as Quantity) + 1 year)
		when choice is Interval<Quantity> then
		  Interval[Patient.birthDate + (choice.low as Quantity),
			  Patient.birthDate + (choice.high as Quantity) + 1 year)
		when choice is Timing then
      Message(null, true, 'NOT_IMPLEMENTED', 'Error', 'Calculation of an interval from a Timing value is not supported') as Interval<DateTime>
		else
			null as Interval<DateTime>
	end