Clinical Trial Cohort Definition and Evaluation with CQL and CDS-Hooks

This repository contains a postman collection and simplified walkthrough of an automated clinical trial patient selection architecture as described here. The following diagram (originally published here) gives an overview of the proposed architecture:

The prerequisite for the walkthrough is for researchers to specify the criteria for the trial. In this example, an existing trial is used so the criteria are already defined. The criteria for the chosen trial are summarized here:

Min Age	Max Age	Gender	Pregnancy Status	Tobacco Use	Inclusion Criteria	Exclusion Criteria
18	N/A	female	true	N/A	Diagnosed Appendicitis	N/A

The criteria can, if available be entered via a UI. In this walkthrough the CQL generation step is omitted. The resulting CQL Library, Measure and Plandefinition are provided directly in the postman collection.

The following walkthrough uses the Postman collection here.

The necessary tools for the following steps are:

• Postman (or similar)
• Docker for local instance of CQF Ruler (alternatively: public HAPI FHIR Server)

Steps

1. Set up \FHIR Server & CQF Ruler To set up a local instance of the CQF Ruler with Docker (1.) enter these commands into the terminal:

   docker pull alphora/cqf-ruler
   docker run -p 8080:8080 alphora/cqf-ruler
   

   or follow the guide here

2. GET metadata to check server requirements

3. POST test resources to the FHIR server

4. POST ClinicalTrials Base Library, FHIRHelpers Library, the example trial Library, and Plandefinition (In real system: Identify criteria and enter via UI)

5. Check cds-hooks endpoint for active cds-services

Result:

{
   "services": [
       {
           "hook": "patient-view",
           "id": "PregnancyAppendicitisClinicalTrialPlanDefinition",
           "prefetch": {
               "item1": "Patient?_id={{context.patientId}}"
           }
       }
   ]
}

7. Trigger cds-hook for different patients

   Result for patient who does not qualify (Patient 1&3)

   {
      "cards": []
   }
   

   Result for patient who qualifies (Patient 2)

   {
      "cards": [
          {
              "summary": "Clinical Trial Qualification",
              "detail": "The Patient qualifies for trial: Laparoscopic Treatment for Appendicitis During Pregnancy",
              "indicator": "info",
              "links": [
                  {
                      "label": "Clinical Trial Details",
                      "url": "https://clinicaltrials.gov/study/NCT04753502",
                      "type": "absolute"
                  }
              ]
          }
      ]
   } 
   
   

8. PUT Measure

9. GET $evaluate-measure operation: The parameter reportType is set to subject-list to get a list of ids of the eligible patients

Result:

{
   "resourceType": "MeasureReport",
   "contained": [
       {
           "resourceType": "List",
           "id": "30c34a37-7043-445a-87f9-3aa58971818b",
           "entry": [
               {
                   "item": {
                       "reference": "clinicalTrials-patient-2"
                   }
               }
           ]
       }
   ],
   "status": "complete",
   "type": "subject-list",
   "measure": "http://cql/Measure/PregnancyAppendicitisClinicalTrialMeasure",
   "date": "2024-03-20T07:15:01+00:00",
   "period": {
       "start": "1923-01-01T00:00:00+00:00",
       "end": "2023-09-16T00:00:00+00:00"
   },
   "group": [
       {
           "population": [
               {
                   "code": {
                       "coding": [
                           {
                               "code": "initial-population"
                           }
                       ]
                   },
                   "count": 1,
                   "subjectResults": {
                       "reference": "#30c34a37-7043-445a-87f9-3aa58971818b"
                   }
               }
           ]
       }
   ]
}