mimic-iii missing ICUstay_IDs, Aren't all of these hospitalizations ICU admits?

Question

Of the 58,976 admissions (hadm_ID's) in the database, 1190 have no associated ICUstay_ID's. How is this possible? Are there hospitalizations in the database that didn't include any ICU admissions?

Answer 1

A patient can be admitted into a hospital ward and not go into ICU.