The Hamilton Depression Rating Scale has proven useful for determining the level of depression before, during, and after treatment.
It is based on the clinician's interview with the patient and probes symptoms such as depressed mood, guilty feelings, suicide, sleep disturbances, anxiety levels and weight loss.
The interview and scoring takes about 15 minutes. The rater enters a number for each symptom construct that ranges from 0 (not present) to 4 (extreme symptoms).
A Rating Scale for Depression
This is the original publication of the HAM-D.