Starter FHIR Implementation Guide
1.0.1 - draft
Starter FHIR Implementation Guide
1.0.1 - draft
Starter FHIR Implementation Guide, published by Jembi Health Systems. This guide is not an authorized publication; it is the continuous build for version 1.0.1 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/jembi/Starter-FHIR-IG/ and changes regularly. See the Directory of published versions
| Draft as of 2024-11-17 |
Definitions for the strict-quantity data type profile.
Guidance on how to interpret the contents of this table can be found here
| 0. Quantity | |
| 2. Quantity.value | |
| Control | 1..? |
| 4. Quantity.unit | |
| Control | 1..? |
| 6. Quantity.system | |
| Control | 1..? |
| 8. Quantity.code | |
| Control | 1..? |
Guidance on how to interpret the contents of this table can be found here
| 0. Quantity | |
| Definition | A measured amount (or an amount that can potentially be measured). Note that measured amounts include amounts that are not precisely quantified, including amounts involving arbitrary units and floating currencies. |
| Short | A measured or measurable amount |
| Comments | The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. |
| Control | 0..* This element is affected by the following invariants: ele-1 |
| Is Modifier | false |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) qty-3: If a code for the unit is present, the system SHALL also be present ( code.empty() or system.exists())qty-3: If a code for the unit is present, the system SHALL also be present (code.empty() or system.exists()) |
| 2. Quantity.value | |
| Definition | The value of the measured amount. The value includes an implicit precision in the presentation of the value. |
| Short | Numerical value (with implicit precision) |
| Comments | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
| Control | 10..1 |
| Type | decimal |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Precision is handled implicitly in almost all cases of measurement. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 4. Quantity.comparator | |
| Definition | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. |
| Short | < | <= | >= | > - how to understand the value |
| Control | 0..1 |
| Binding | The codes SHALL be taken from QuantityComparatorhttp://hl7.org/fhir/ValueSet/quantity-comparator|4.0.1 (required to http://hl7.org/fhir/ValueSet/quantity-comparator|4.0.1)How the Quantity should be understood and represented. |
| Type | code |
| Is Modifier | true because This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology. |
| Meaning if Missing | If there is no comparator, then there is no modification of the value |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 6. Quantity.unit | |
| Definition | A human-readable form of the unit. |
| Short | Unit representation |
| Control | 10..1 |
| Type | string |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 8. Quantity.system | |
| Definition | The identification of the system that provides the coded form of the unit. |
| Short | System that defines coded unit form |
| Control | 10..1 This element is affected by the following invariants: qty-3 |
| Type | uri |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Need to know the system that defines the coded form of the unit. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 10. Quantity.code | |
| Definition | A computer processable form of the unit in some unit representation system. |
| Short | Coded form of the unit |
| Comments | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
| Control | 10..1 |
| Type | code |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
Guidance on how to interpret the contents of this table can be found here
| 0. Quantity | |
| Definition | A measured amount (or an amount that can potentially be measured). Note that measured amounts include amounts that are not precisely quantified, including amounts involving arbitrary units and floating currencies. |
| Short | A measured or measurable amount |
| Comments | The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. |
| Control | 0..* This element is affected by the following invariants: ele-1 |
| Is Modifier | false |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))qty-3: If a code for the unit is present, the system SHALL also be present ( code.empty() or system.exists()) |
| 2. Quantity.id | |
| Definition | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. |
| Short | Unique id for inter-element referencing |
| Control | 0..1 |
| Type | string |
| Is Modifier | false |
| XML Format | In the XML format, this property is represented as an attribute. |
| Summary | false |
| 4. Quantity.extension | |
| Definition | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. |
| Short | Additional content defined by implementations |
| Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
| Control | 0..* |
| Type | Extension |
| Is Modifier | false |
| Summary | false |
| Alternate Names | extensions, user content |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))ext-1: Must have either extensions or value[x], not both ( extension.exists() != value.exists()) |
| Slicing | This element introduces a set of slices on Quantity.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators: |
| 6. Quantity.value | |
| Definition | The value of the measured amount. The value includes an implicit precision in the presentation of the value. |
| Short | Numerical value (with implicit precision) |
| Comments | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
| Control | 1..1 |
| Type | decimal |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Precision is handled implicitly in almost all cases of measurement. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 8. Quantity.comparator | |
| Definition | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. |
| Short | < | <= | >= | > - how to understand the value |
| Control | 0..1 |
| Binding | The codes SHALL be taken from QuantityComparator (required to http://hl7.org/fhir/ValueSet/quantity-comparator|4.0.1)How the Quantity should be understood and represented. |
| Type | code |
| Is Modifier | true because This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology. |
| Meaning if Missing | If there is no comparator, then there is no modification of the value |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 10. Quantity.unit | |
| Definition | A human-readable form of the unit. |
| Short | Unit representation |
| Control | 1..1 |
| Type | string |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 12. Quantity.system | |
| Definition | The identification of the system that provides the coded form of the unit. |
| Short | System that defines coded unit form |
| Control | 1..1 This element is affected by the following invariants: qty-3 |
| Type | uri |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Need to know the system that defines the coded form of the unit. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
| 14. Quantity.code | |
| Definition | A computer processable form of the unit in some unit representation system. |
| Short | Coded form of the unit |
| Comments | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
| Control | 1..1 |
| Type | code |
| Is Modifier | false |
| Primitive Value | This primitive element may be present, or absent, or replaced by an extension |
| Summary | true |
| Requirements | Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest. |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |