CBT vs. Medication: Comparing Effect Sizes for Anxiety Disorders

When patients seek treatment for anxiety disorders, they often face a choice between psychotherapy and medication. This article examines the scientific evidence comparing the effectiveness of online cognitive-behavioral therapy (CBT) versus medication (specifically SSRIs and SNRIs) across five common anxiety disorders.

Reliable Change in Psychotherapy Over Sessions

Understanding Effect Sizes

The chart displays standardized mean differences (SMD), a statistical measure that allows us to compare the effectiveness of different interventions. An SMD of 0.2 is considered small, 0.5 is medium, and 0.8 or above is large. Higher values indicate greater effectiveness in reducing symptoms.

Key Findings by Disorder

Panic Disorder

  • Online CBT: Very large effect (SMD = 1.31)1
  • Medication: Small effect (SMD = 0.30)4

Online CBT shows a dramatically larger effect size for panic disorder compared to medication, with more than four times the impact on symptom reduction. This difference is particularly noteworthy and suggests that CBT may be the treatment of choice for this condition.

Social Anxiety Disorder

  • Online CBT: Large effect (SMD = 0.92)1
  • Medication: Medium effect (SMD = 0.67)4

While both treatments show substantial efficacy for social anxiety, online CBT demonstrates a notably stronger effect. This condition appears to respond well to both intervention types.

Obsessive-Compulsive Disorder

  • Online CBT: Medium-large effect (SMD = 0.75)2
  • Medication: Medium effect (SMD = 0.59)4

Both treatments show meaningful effects for OCD, with online CBT holding a modest advantage. The combination of these approaches may be particularly beneficial for this often-challenging condition.

Post-Traumatic Stress Disorder

  • Online CBT: Medium-large effect (SMD = 0.71)3
  • Medication: Small-medium effect (SMD = 0.42)4

PTSD shows a more substantial response to CBT interventions, though medications still offer meaningful benefit. The trauma-focused nature of CBT may explain its stronger performance.

Generalized Anxiety Disorder

  • Online CBT: Medium-large effect (SMD = 0.70)1
  • Medication: Medium effect (SMD = 0.55)4

Both treatment modalities demonstrate respectable efficacy for GAD, with CBT showing a modest advantage.

Clinical Implications

Several important patterns emerge from this data:

  1. CBT outperforms medication across all anxiety disorders. The advantage ranges from modest (GAD, OCD) to substantial (panic disorder).

  2. Accessibility matters. The fact that these strong effect sizes come from online CBT suggests that effective treatment need not be limited by geographic or scheduling constraints.

  3. Disorder-specific considerations. The differential effectiveness across disorders suggests that treatment selection should be tailored to the specific condition.

  4. Combination potential. Since these interventions work through different mechanisms, combining them may offer additive benefits, particularly for conditions like OCD.

Practical Considerations

While effect sizes offer valuable guidance, treatment decisions should also consider:

  • Individual preferences and treatment history
  • Access and cost considerations
  • Time commitment (CBT typically requires active participation)
  • Side effect profiles (medications may have physiological side effects)
  • Comorbid conditions that might influence treatment selection

The strong performance of online CBT across all anxiety disorders makes it a compelling first-line option, particularly for patients who prefer non-pharmacological approaches or have concerns about medication side effects.

Literature

  1. Andrews, G., Basu, A., Cuijpers, P., Craske, M. G., McEvoy, P., English, C. L., & Firth, J. (2018). Computer therapy for the anxiety and depression disorders is effective, acceptable and practical health care: An updated meta-analysis. Journal of Anxiety Disorders, 55, 70-78.
  2. Polak, M., & Tanzer, N. K. (2024). Internet‐Based Cognitive Behavioural Treatments for Obsessive–Compulsive Disorder: A Systematic Review and Meta‐Analysis. Clinical Psychology & Psychotherapy, 31(3), e2989.
  3. Sijbrandij, M., Kunovski, I., & Cuijpers, P. (2016). Effectiveness of internet‐delivered cognitive behavioral therapy for posttraumatic stress disorder: A systematic review and meta‐analysis. Depression and Anxiety, 33(9), 783-791.
  4. Gosmann, N. P., Costa, M. A., Jaeger, M. B., Motta, L. S., Frozi, J., Spanemberg, L., & Manfro, G. G. (2021). Selective serotonin reuptake inhibitors, and serotonin and norepinephrine reuptake inhibitors for anxiety, obsessive-compulsive, and stress disorders: A 3-level network meta-analysis. PLoS Medicine, 18(6), e1003664.