@Christian_Reich, @bailey, @wstephens and All,
For our part, we are working with an assessment instrument called the Minimum Data Set that is interesting to represent in the CDM for the following reasons:
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It is a nurse assessment done periodically and so in principal contains observations - so would not fit in any measurement types I saw listed above.
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Patient conditions from the patient charts are listed as ICD codes that can go into the condition table
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The assessments contain both validated psychometric scales such BIMS (cognitive status) and PHQ-9 (depressive symptoms) which result in something like measurements (quantitative scores) but that also can be interpreted as conditions based on expert guidelines (e.g., depression if PHQ-9 score > X)
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LOINC (and standard vocab) has codes for all of the questions such as 40757755 = “Cognitive skills for daily decision making in last 7 days MDSv3”.
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LOINC has answer codes for the questions that are not yet in the standard vocab (hence our discussion! Are surveys measurements or observations?)
Wrt to the question about placing survey items in measurements. Based on our limited experience, we might propose that values from any psychometric scale be treated as observations, regardless of the value types.
This is how we do it now - our working interpretation is that all MDS data except the conditions be coded as observations using the concept ids for LOINC question codes and answers (once in). Business rules in our ETL are then applied to translate the subset of observations from validated psychometric scales that can be interpreted as conditions. For example, major depression if found by PHQ-9 because, in general, this treated clinically as lasting condition from which a patient could have remission.
-Rich and Yifan