I am working on an ETL of ICU data gotten through a questionnaire. During my Rabbit in a Hat mapping I felt I needed some guidance as to where to put boolean (1 and 0 in the database) fields that are basically observations derived from measurements.
Some examples:
- When sepsis was suspected, did the patient have leukopenia? (Leukopenia is defined as having a leukocyte count less than 4*10^9/L)
- When sepsis was suspected, was the arterial pCO2 value lower than 32 mm Hg (4.3 kPa)?
- Did the patient get kidney replacement therapy in the first 24 hours of being admitted to the ICU?
Do these binary/boolean fields belong to the OBSERVATION table mapped to value_as_a_string or value_as_a_number? Or does the first one belong in the CONDITION_OCCURANCE table? Or do the first two maybe even belong the MEASUREMENT table? And do I map the third in PROCEDURE_OCCURENCE as procedure_source_value?