Diagnosis of Depression
Diagnosis of depression involves a comprehensive evaluation of emotional, psychological, and physical symptoms. Since depression manifests differently in each person, an accurate and timely diagnosis is crucial for guiding appropriate treatment. Mental health professionals use various clinical tools and assessments to determine the presence, type, and severity of the condition.
Initial Consultation and History Taking
The diagnostic process begins with a detailed consultation:
The GP or mental health professional will ask about mood changes, thought patterns, sleep habits, and daily functioning
Patients may be asked about family history, recent stressors, or any substance use
It’s important to discuss how long symptoms have lasted and whether they interfere with work, relationships, or self-care
Open, honest communication during this stage is vital. Many people downplay their symptoms, but even mild or intermittent signs can indicate clinical depression.
Diagnostic Criteria
The most commonly used diagnostic frameworks are:
DSM-5 (Diagnostic and Statistical Manual of Mental Disorders) by the American Psychiatric Association
ICD-11 (International Classification of Diseases) by the World Health Organization
To meet the criteria for major depressive disorder, at least five symptoms must be present for two weeks or more, and at least one must be either:
Depressed mood
Loss of interest or pleasure
Other possible symptoms include fatigue, appetite changes, insomnia, feelings of worthlessness, difficulty concentrating, and suicidal thoughts.
Depression Screening Tools
Clinicians may use validated questionnaires such as:
PHQ-9 (Patient Health Questionnaire): Rates the severity of symptoms
Beck Depression Inventory (BDI)
Hamilton Rating Scale for Depression (HAM-D)
These tools help quantify symptoms and monitor progress over time.
Physical Examination and Tests
Since physical illnesses can mimic or contribute to depression, a GP may conduct:
Blood tests to check for thyroid issues, vitamin deficiencies, or anaemia
Neurological examination to rule out conditions like Parkinson’s or early dementia
Differential Diagnosis of Depression
It’s essential to distinguish depression from:
Bipolar disorder
Anxiety disorders
Chronic fatigue syndrome
Grief or bereavement (which may not require clinical intervention)
In summary, diagnosis of depression requires a holistic evaluation combining symptom analysis, mental health assessments, and physical health checks. Accurate diagnosis is the foundation for effective, personalised treatment.
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