This page is part of the Retrieval of Real World Data for Clinical Research (v1.0.0: STU1) based on FHIR R4. This is the current published version in its permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions
The following use case was used to determine the requirements for determining a patient cohort along with what data elements were necessary when retrieving clinical data:
The details of this study can be found on ClinicalTrials.gov: NCT04848584.
The primary objective of this study is to determine the vaccine effectiveness of 2 doses of Pfizer-BioNTech BNT162b2 vaccine against COVID-19-associated hospitalization. There will be a large retrospective database study using two parallel study designs: a test-negative case-control design and a retrospective cohort design. Exploratory analyses of VE estimates by strain type will be conducted.
The patients for this study would have the following criteria:
These criteria would be represented by the following queries:
/Patient?birthdate=le<birthdate of 5 years before today>&gender=male,female
/Condition?code:in=http://hl7.org/fhir/uv/vulcan-rwd/ValueSet/ExampleRespiratoryConditionCodes
/Observation?status=final&code:in=http://hl7.org/fhir/uv/vulcan-rwd/ValueSet/ExampleCOVID19TestCodes
The patients would also not have the following criteria:
This exclusion criteria would be represented by the following query:
/Immunization?status=completed&vaccine-code:in=http://hl7.org/fhir/uv/vulcan-rwd/ValueSet/ExampleNonBNT162b2Codes
The patients that were common to the first three queries and were not found in the exclusion query would form the set of patients representing this cohort.
For patients that meet the criteria above, the following data, as a minimum, would be retrieved: