diagnostic criteria for depression

Last reviewed 09/2021

Diagnostic criteria for depression

NICE adopted the DSM-IV criteria rather than the ICD-10 criteria for diagnosis of depression:

DSM versus ICD-10 classification

• DSM-IV is used in nearly all clinical trials and it provides definitions for atypical symptoms and seasonal depression
  • its definition of severity also makes it less likely that a diagnosis of depression will be based solely on symptom counting
  • NICE though favouring DSM-IV note that clinicians are not expected to switch to DSM-IV but should be aware that the threshold for mild depression is higher than ICD-10 (five symptoms instead of four) and that degree of functional impairment should be routinely assessed before making a diagnosis

Assessment of depression is based on the criteria in DSM-IV. Assessment should include the number and severity of symptoms, duration of the current episode, and course of illness. Key symptoms:

• persistent sadness or low mood; and/or
• marked loss of interests or pleasure
• at least one of these, most days, most of the time for at least 2 weeks
  
  
• if any of above present, ask about associated symptoms:
  • disturbed sleep (decreased or increased compared to usual)
  • decreased or increased appetite and/or weight
  • fatigue or loss of energy
  • agitation or slowing of movements
  • poor concentration or indecisiveness
  • feelings of worthlessness or excessive or inappropriate guilt
  • suicidal thoughts or acts
    
    
• the duration and associated disability, past and family history of mood disorders, and availability of social support should also be asked about:
  
  
  • 1. factors that favour general advice and active monitoring:
    • four or fewer of the above symptoms with little associated disability
    • symptoms intermittent, or less than 2 weeks' duration
    • recent onset with identified stressor
    • no past or family history of depression
    • social support available
    • lack of suicidal thoughts
  • 2. factors that favour more active treatment in primary care:
    • five or more symptoms with associated disability
    • persistent or long-standing symptoms
    • personal or family history of depression
    • low social support
    • occasional suicidal thoughts
  • 3. factors that favour referral to mental health professionals:
    • inadequate or incomplete response to two or more interventions
    • recurrent episode within 1 year of last one
    • history suggestive of bipolar disorder
    • the person with depression or relatives request referral
    • more persistent suicidal thoughts
    • self-neglect
  • 4. factors that favour urgent referral to specialist mental health services
    • actively suicidal ideas or plans
    • psychotic symptoms
    • severe agitation accompanying severe symptoms
    • severe self-neglect.

DSM-IV severities of depression

• subthreshold depressive symptoms: Fewer than 5 symptoms
• Mild depression: few, if any, symptoms in excess of the 5 required to make the diagnosis, and symptoms result in only minor functional impairment
• Moderate depression: symptoms or functional impairment are between 'mild' and 'severe'
• Severe depression: most symptoms, and the symptoms markedly interfere with functioning. Can occur with or without psychotic symptoms.

Reference:

• 1) NICE (October 2009). Depression