| ICD-9-CM: |
| 296.2 - | Major Depressive Disorder, Single Episode |
| 296.20 - | Major Depressive Disorder, Single Episode; Unspecified |
| 296.21 - | Major Depressive Disorder, Single Episode; Mild |
| 296.22 - | Major Depressive Disorder, Single Episode; Moderate |
| 296.23 - | Major Depressive Disorder, Single Episode; Severe, without Mention of Psychotic Behavior |
| 296.24 - | Major Depressive Disorder, Single Episode; Severe, Specified as with Psychotic Behavior |
| 296.25 - | Major Depressive Disorder, Single Episode; in Partial or Unspecified Remission |
| 296.26 - | Major Depressive Disorder, Single Episode; in Full Remission |
| 296.3 - | Major Depressive Disorder, Recurrent Episode |
| 296.30 - | Major Depressive Disorder, Recurrent Episode; Unspecified |
| 296.31 - | Major Depressive Disorder, Recurrent Episode; Mild |
| 296.32 - | Major Depressive Disorder, Recurrent Episode; Moderate |
| 296.33 - | Major Depressive Disorder, Recurrent Episode; Severe, without Mention of Psychotic Behavior |
| 296.34 - | Major Depressive Disorder, Recurrent Episode; Severe, Specified as with Psychotic Behavior |
| 296.35 - | Major Depressive Disorder, Recurrent Episode; in Partial or Unspecified Remission |
| 296.36 - | Major Depressive Disorder, Recurrent Episode; in Full Remission |
| 311 - | Depressive Disorder, Not Elsewhere Classified |