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What is the usage of min_levels_of_separation and max_levels_of_separation?

(whg) #1

Iknow the fields of min_levels_of_separation and max_levels_of_separation are levels of separation represent the number of steps from an ancestor to a descendant.
What are the application scenarios?
Some examples will be helpful.

(Christian Reich) #2

Usually, min_levels_of_separation is used. It is a good approximation of the “degree of relation”. So, if you want to have the next level up you pick 1 level. Or you sort ancestors or descendants by the level of separation for browsing purposes.

Why are you asking?

(whg) #3

I’ve just learned about CDM and am learning about the application scenarios for each field.
we have the CONCEPT_RELATIONSHIP table to define direct relationships between any two Concepts.so only when we want to find more than one level ancestry or descendant,the table CONCEPT_ANCESTOR is used.

(Christian Reich) #4

You may want to read the Book of OHDSI.