I am also working on mapping survey data to the OMOP-CDM - on the EHDEN.eu project. I am mapping an ICHOM standard set (i.e. Survey results) to the OMOP-CDM and hope you can help me with the following questions.
• In the conventions for the OBSERVATION table it says that “Valid Concepts of the VALUE_AS_CONCEPT field are not enforced, but typically belong to the ‘Meas Value’ domain”. When using the OBSERVATION table for survey responses, these will then typically be from the ‘Observation’ domain. Do I understand this correctly?
• When using USAGI to generate mappings of question-responses to existing standard concepts, the suggested mappings vary between domains. For example, the two questions below are establishing the presence of prior heart or lung disease and these are USAGI’s best-guess.
Source Description Target Concept_ID Target Description Vocabulary Domain
Other heart disease 45879053 Other heart disease LOINC Meas Value
Chronic lung disease 4188164 History of chronic lung disease SNOMED Observation
My question: What criteria should be used for selecting the best match for a survey question-answer? Would you focus on description? Are Vocabulary & Domain important?
• If all the question-answers are stored in the OBSERVATION table – including those that might also be expected to be in the CONDITION_OCCURRENCE table (such as the two above), will this make the information difficult to find for others?
• A related question: How would one distinguish the source of the answer to the above two questions? e.g. a patient response, a link to an EHR record, a medical professional assessment on-the-spot.
I would be happy if you can point me to information that might help me here.