(nature, etc.) observation diary
(medical) follow-up; observation
observation room (in a hospital, police station, etc.)
(verbal) health check (esp. in elementary school, during roll call); health monitoring (e.g. of travelers during a quarantine period)
medical observation (esp. of emerging diseases by the Chinese authorities)
Medical Observation Act; Act on Medical Care and Treatment for Persons Who Have Caused Serious Cases Under the Condition of Insanity