Which is a lab test done to help diagnose diabetes insipidus?

A key lab test used to help diagnose Diabetes insipidus is the water deprivation test. This test assesses the body's ability to concentrate urine in response to dehydration. Patients are deprived of water for a certain period, and their urine output and concentration are measured. If the urine remains dilute despite dehydration, it may indicate diabetes insipidus.