To effectively assess the severity of obsessive-compulsive disorder (OCD) symptoms in a primary care setting, healthcare professionals should begin with a thorough clinical interview that explores the presence, frequency, and impact of obsessions and compulsions. Direct questions such as "Do you wash or clean a lot?", "Do you check things a lot?", and "Is there any thought that keeps bothering you that you would like to get rid of but cannot?" help identify symptom presence and distress NICE CG31.
Assessment should include evaluating the degree of functional impairment caused by OCD symptoms, considering how much the symptoms interfere with daily activities, work, or social interactions NICE CKS. The impact on the patient’s life and the time consumed by compulsive behaviors are key indicators of severity NICE CG31.
Risk assessment is critical, especially for self-harm and suicide, particularly if comorbid depression is present. Patients with intrusive sexual, aggressive, or death-related thoughts require careful evaluation, and if uncertainty exists, consultation with or referral to a specialist is advised NICE CG31,NICE CKS.
Using standardized tools such as the Yale–Brown Obsessive-Compulsive Scale (Y-BOCS) or questions derived from it can provide a structured measure of symptom severity and allow comparison over time NICE CKS.
In addition, assessing comorbidities (e.g., anxiety, depression, substance misuse) and psychosocial factors is important as they may influence severity and treatment needs NICE CG31.
Involving family members or carers in the assessment can provide additional insight into the impact of OCD symptoms and the extent of functional impairment NICE CG31.
For patients with mild functional impairment, low-intensity psychological interventions may be appropriate, while those with moderate to severe impairment should be considered for referral to specialist mental health services NICE CKS.
Recent meta-analytic evidence supports the use of cognitive-behavioral therapy (CBT), including exposure and response prevention (ERP), as an effective treatment, underscoring the importance of accurate severity assessment to guide appropriate intervention [Öst et al., 2022].