Accurate diagnosis of any individual's specific depression symptoms will provide clarity for how to approach treatment. An individual who suffers from mental fatigue might approach different treatment(s) (like meditation) than one with excessive mental stimulation (who might take Kava to slow the mind down). Similarly, someone showing signs of insomnia would be treated differently (perhaps with chamomile and a change in diet) than one who oversleeps (who might need exercise to energize them!).
As a first step in the diagnosis of Major Depressive Disorder, a clinical psychologist look for the occurrence of the following signs of depression in an individual:1
A. Exhibiting 5 (or more) out of the following symptoms when they have been present during the same two-week period and represent a change from previous functioning. (At least one of the symptoms must be either (1) depressed mood or (2) loss of interest or pleasure):
- Depressed mood most of the day, nearly every day NOTE: In children and adolescents, it can be irritable mood
- Markedly diminished interest or pleasure in all, or almost all activities most the day, nearly every day
- Significant weight loss (when not dieting) or weight gain, or decrease or increase in appetite NOTE: In children, consider failure to make expected weight gains
- Insomnia or hypersomnia nearly every day
- Psychomotor agitation or retardation nearly every day
- Fatigue or loss of energy nearly every day
- Feelings of worthlessness or excessive or inappropriate guilt nearly every day
- Diminished ability to think or concentrate, or indecisiveness, nearly everyday
- Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or specific plan for committing suicide
[Persistent aches or pains, headaches, cramps or digestive problems that do not ease even with treatment may also be assessed by a clinician and indicative of depressive symptoms.]1
B. The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning
C. The symptoms are not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition
D. The symptoms are not better accounted for by Bereavement, i.e., after the loss of a loved one, the symptoms persist for longer than 2 months or are characterized by marked functional impairment, morbid preoccupation with worthlessness, suicidal ideation, psychotic symptoms, or psychomotor retardation.
In Major Depressive Disorder, the depressed mood must be present for most of the day, nearly every day, for a period of at least 2 weeks. Should a person experience a "Single Episode," these symptoms wold only be present for one period of time (around 2 weeks worth). An individual who suffers form "Recurrent," Major Depressive Episodes can experience periods of major depression throughout life.
While an actual diagnosis of depression must come from a doctor or mental health physician, there are many psychological tests that can indicate the presence, and in some cases the severity, of certain depression symptoms. Many tests are available online, others are only used in the research setting, and some are used by practitioners to help with the diagnosis. All test the prevalence (by yes/no questions) and/or severity (by scaled answer options) of symptoms 1-9 listed above.
Test scores can be part of the initial evaluation of depression with a physician and can even prompt individuals to see a physician if they take the test at home. Tests can be used to measure patient progress during and after treatment. Additionally, these tests are often used by researchers conducting studies (given before and after the study) to evaluate the efficacy of their hypothesis.
Some well-known tests include:
- Beck Depression Inventory
- Hamilton Rating Scale for Depression (HAM-D)
- Geriatric Depression Scale
- Quick Inventory of Depressive Symptoms (QIDS)
- Hospital Anxiety and Depression Scale
- Symptom Checklist (SCL)
- State-Trait Anxiety Inventory
Many additional tests address specific depression symptoms such as anxiety, sleep and anger. Sometimes physiological measures (including heart rate variability, blood pressure and cortisol levels) are measured to indicate the severity of certain depression symptoms such as anxiety; these are usually used when conducting a depression study. The aforementioned well-known tests however, address myriad symptoms which can comprehensively indicate a potential depression diagnosis.
When taking an online test for depression, it is important to consider how legitimate and who is funding the test, and to remember that test results cannot replace an actual physician diagnosis.
- American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders, fourth edition: Text revision. Washington DC: Author.
- Preston, J. D., O'Neal, J. H., & Talaga, M. C. (2005). Handbook of clinical psychopharmacology for therapists. Oakland, CA: New Harbinger Publications, Inc.