--- type: "fhirpath-function" title: "FHIRPath Function: allFalse" function: "allFalse" category: "Existence" section: "5.1.6" source: "fhirpath/functions.json" --- # FHIRPath Function: allFalse Takes a collection of Boolean values and returns `true` if all the items are `false`. If any items are `true`, the result is `false`. If the input is empty (`{ }`), the result is `true`. The following example returns `true` if none of the components of the Observation have a value greater than 90 mm[Hg]: ``` fhirpath Observation.select(component.value > 90 'mm[Hg]').allFalse() ``` ## Summary - **Category**: Existence - **Section**: `5.1.6` - **Return Type**: `Boolean` - **Empty Input Result**: `true` - **Errors on Multiple Input**: `false` ## Description Takes a collection of Boolean values and returns `true` if all the items are `false`. If any items are `true`, the result is `false`. ## Arguments - none ## Type Mapping - `Boolean-Boolean` ## Example ```fhirpath Observation.select(component.value > 90 'mm[Hg]').allFalse() ```