To determine the reliability and diagnostic performance of the GAD-7 and GAD-2 for prevalent anxiety disorders in Latvian primary care using the Mini International Neuropsychiatric Interview (MINI) as the reference standard.
Approach:
Participants: Consecutive adult patients from 24 primary care practices completed the GAD-7 and GAD-2 prior to consultation.
Assessment: Blinded psychiatrists conducted MINI interviews by telephone within two weeks of the initial consultation.
Analysis: Internal consistency was assessed using Cronbach’s alpha; diagnostic accuracy was evaluated using receiver operating characteristic analyses, sensitivity, specificity, and likelihood ratios.
Key Findings:
The final analytical sample comprised 1,467 participants.
Most prevalent MINI-defined anxiety disorders were agoraphobia (8.0%), generalized anxiety disorder (6.1%), and social phobia (4.7%).
Internal consistency was 0.86 for the GAD-7 and 0.72 for the GAD-2.
For generalized anxiety disorder, optimal cut-offs were ≥6 (GAD-7; sensitivity 71.9%, specificity 76.3%, AUC = 0.799) and ≥2 (GAD-2; sensitivity 80.9%, specificity 65.8%, AUC = 0.772).
Performance for social phobia, agoraphobia, and any anxiety disorders was relatively weak.
For any anxiety disorder, the optimal thresholds were identified as ≥4 (GAD-7; sensitivity 70.6%, specificity 61.6%, AUC = 0.718) and ≥2 (GAD-2; sensitivity 64.9%, specificity 68.1%, AUC = 0.691).
Interpretation:
The GAD-7 and GAD-2 demonstrate satisfactory reliability and diagnostic accuracy for screening generalized anxiety disorder in Latvian primary care.
Limitations:
Performance for other anxiety disorder subtypes was comparatively limited.
Specific cut-offs for different anxiety disorders were not calculated.
Conclusion:
Subtypes of anxiety disorders should be considered, and specific cut-offs calculated to improve detection in routine general practice.
