The purpose of diagnoses

When we diagnose a person with a psychological disorder, it’s purpose is not to create stigma or to generate as many potential diagnoses as possible and label somebody with every disorder under the sun.

Diagnoses are meant to be helpful.

They are way to understand a person’s current challenges and determine the best way to conceptualize the constellation of different symptoms under a diagnosis. Diagnoses then guide us to make hypotheses on potential causes of these symptoms and allow us to determine potential treatment options.

Proper diagnoses are therefore essential in hypotheses-generating and treatment planning.

Ways to diagnose clinical depression

The problem with assessing for mental health challenges is that there are no clear ‘biomarkers’ when it comes to depression. Simply put, this means that there is no brain activation, neurotransmitter, or hormonal patterns that definitively conclude depression (Deacon, 2013). Although there are certain chemicals that are related to depression, such as serotonin (Moncrieff et al., 2022), these studies have primarily been correlational. This means that they are related, but low serotonin does not necessarily mean depression.

Self-reports (using questionnaires) can be helpful in ensuring good reliability between each person’s responses. However, the problem is that it loses some of the individual perspectives that may be very important to understand when considering the unique nature of each person’s depression.

Because of these limitations, semistructured clinical interviews are the current gold standard for assessment by clinical psychologists because they offer a subjective report from the person who is experiencing the symptoms.

The flexibility of the interviews allows each individual to share their personal experience, while the specific questions help with increasing reliability to make sure we are reducing bias and asking the right questions associated with symptoms of depression. Moreover, by getting the person’s specific story, then we may be able to start thinking about what might be causing the person’s depression (and possible treatments that might the best to tackle them).

Semi-structured interviews, such as the SCID-5 (Structured Clinical Interview for DSM-5) and the DART (Diagnostic Assessment Research Tool) are often used to support diagnoses

Diagnostic criteria for depression

There are 9 symptoms to meet criteria for a major depressive episode. They must be present for at least two weeks and at least one of the symptoms must be 1) depressed mood or 2) loss of interest.

1. Depressed mood.The person usually feels depressed, sad, hopeless, and/or empty in terms of their general mood over a significant period of time.

2. Loss of interest. The person usually find that they find less pleasure in activities they use to enjoy (also known as ‘anhedonia’).

3. Difficulty sleeping / sleeping too much. For example, sleeping 6 hours when the person used to sleep 8; or sleeping for 10 hours (and still feeling unrefreshed)

4. Changes in appetite or weight. The person may find that they are over or undereating. They may also notice changes in their weight without intentionally wanting to lose or gain weight.

5. Guilt or worthlessness. The person may feel worthless or guilty for things they did or did not do. When it comes to guilt, they must be about things that people may normally not feel guilty for (e.g., guilty for not being able to work even when they were sick).

6. Fatigue. People with depression may also feel tired all day, lacking any energy.

7. Difficulty concentrating. The person may also have trouble making everyday decisions, such as choosing what clothes to wear, what groceries to buy, among other tasks.

8. Psychomotor agitation/slowing. The person may engage in restless behaviours (e.g., feeling very jittery and agitated); or vice versa, feeling very slow, like they are moving through molasses.

9. Suicidal ideation. Finally, the person may have passive (not wanting to live) or active thoughts (about death

Additional diagnostic considerations during semistructured interviews

Beyond meeting criteria for at least 5 symptoms, there are a few additional considerations that clinical psychologists evaluate when making a diagnosis for depression.

  • Duration. The depressive episode needs to have lasted at least 2 weeks
  • Pervasiveness. The symptoms should be present most of the day, nearly every day. When I have conducted semi-structured interviews, the criteria was informally at least 10 out of the past 14 days.
  • Impairment/distress. The symptoms must be affecting a person’s daily life (e.g., affecting their social life, their work life, hobbies, etc.) or causing significant distress.
  • Other medical conditions. There can be other medical conditions, such as thyroid issues, that can lead to depression symptoms. Therefore, it’s important to assess whether another condition is the main cause of these symptoms.

Common differential diagnoses for depression

Normal sadness. We do not want to pathologize a normal response to loss. And sadness is a normal response when we experience loss (e.g., loss of a romantic relationship, not getting into a school that you wanted to get into). Consequently, depression diagnosis must be significantly above and beyond the symptoms of the typical response to a similar situation.

Although there’s no exact science for how this distinction is measured, there are a few aspects we can consider. For example, normal sadness may not last as long as depression (failing an exam might make someone upset for a few days to a week, but not for months), it may be less impairing to their daily life (e.g., people can still get their daily tasks done), and may be less pervasive (feeling sad for a couple hours rather than feeling empty and hopeless the entire day).

Grief. Grief that results from a loved one’s passing can have distinct qualities to depression. For example, grief tends to come in waves – pangs of sadness with periods where the person feels okay. On the other hand, depression tends to be much more consistent in terms of mood and the feelings may be more associated with emptiness and hopelessness. This post may be helpful if you’d like to dive deeper into the difference between grief and depression.

Bipolar disorders. Bipolar disorders differ from depression in that both bipolar and depressive disorders usually have depressive episodes, but bipolar disorders require the presence of hypo(manic) episodes. These are usually prolonged periods of time where the person feels excessively elevated (e.g., feeling like they are on top of the world) or excessively irritated (picking fights with random strangers). When a person meets criteria for these episodes, then a bipolar diagnosis may be more relevant.

Treatments of clinical depression

Although treatments are beyond the scope of this post, common treatments of depression include medication (e.g., different classes of antidepressants) and therapy. Therapies can include cognitive behavioural therapy, behavioural activation (which can include scheduling activities to increase positive reinforcement), interpersonal therapy, and mindfulness practices.

It is encouraged to speak with your primary care provider or a mental health professional to be properly assessed in order to get the proper treatment for you.

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Best wishes,