Determine if antidepressant treatment guided by pharmacogenetic algorithm and interpretive report improves outcomes when compared with standard treatment without the availability of genetic information.

This study is designed to evaluate the clinical impact of pharmacogenetic (PGx)-directed treatment, as guided by interpretive, algorithmic report in the Pine Rest outpatient behavioral health clinics. The PGx algorithm utilized in this study is the foundation of a novel method of interpreting genetic testing results and reports them in a rapidly delivered format that provides enhanced guidance to psychiatrists in their selection of antidepressant medications

Inclusion Criteria:

• Diagnosis of Major Depressive Disorder (296.2, 296.3) or Depressive Disorder NOS (311.0) by a board certified psychiatrist.
• The patient is referred to the study by their treating psychiatrist or nurse practitioner who is approved by the study investigators to make subject referrals to the study.
• The patient is an outpatient and not in imminent need of inpatient hospitalization for medical or psychiatric reasons.
• Patient's baseline 17-Item Hamilton Depression (HAMD17) Rating score is >14.
• Provide a copy of a physical exam report performed within 6 months prior to study enrollment or undergo a physical exam by either their personal physician, a physician who is a subinvestigator on the study, or a study-contracted physician assistant in internal medicine.
• Undergo a medical history that includes a review of major organ systems by either their treating clinician, a subinvestigator physician, or a study-contracted physician assistant in internal medicine.
• The patient has signed the study informed consent form.

Exclusion Criteria:

• Serious medical illness (as ascertained via inclusion criteria 6 and 7, above).
• Diagnosis of a Bipolar Disorder.
• Diagnosis of Schizophrenia or Schizoaffective disorder.
• Evidence from history, baseline urine drug screen, and/or psychiatric interview of active abuse of alcohol and/or other drugs of abuse within 6 months prior to study enrollment. Patients who occasionally use marijuana may still be eligible if it is determined through psychiatric interview that the level of use does not qualify as abuse, dependence, or addiction. Patients testing positive for opioids or benzodiazepines are eligible if there is no evidence of abuse and it is determined that they are taking opioid analgesics or a benzodiazepine that is prescribed by a licensed prescriber for a medical or psychiatric indication.
• History of prior pharmacogenomic testing.