Use case: Let WB1 be Maternal blood with the requirement name as ‘Maternal'. Let WB2, WB3, etc. be Cord blood with the requirement name as 'Cord’. If you now want a report from OpenSpecimen where you need to know if the aliquots (planned/unplanned) created under these blood specimens are maternal or cord, you can use this type of query to differentiate between the child specimens.
Steps:
Navigate to 'Queries'.
Click on '+Create.'
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Add required filters:
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Click on ‘View Records' → Actions → Columns
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Open 'Specimen' form → Ancestor Requirements
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Save the query.
The aliquot’s SR Name and Code will also be visible in the query because in computer science every node is an ancestor of self. This makes implementations efficient and easy to prove.