Question 1

How reliable is a GAD diagnosis, and what makes it different from normal worry?

Accepted Answer

GAD achieved an intraclass kappa of just 0.20 in the DSM-5 field trials — two clinicians agreed only 20% more often than chance. The unreliability stems from unstructured clinical interviews, not the criteria themselves: structured interviews like the ADIS-5 rebound reliability into the 'good' to 'excellent' range. GAD requires excessive worry more days than not for 6+ months with 3+ of 6 symptoms (adults) or 1+ symptom (children). The 6-month criterion helps distinguish persistent GAD from transient stress reactions.

Question 2

Why is GAD's inter-rater reliability so poor (kappa 0.20) compared to other anxiety disorders?

Accepted Answer

GAD achieved an intraclass kappa of just 0.20 in the DSM-5 field trials — two clinicians agreed only 20% more often than chance. The unreliability stems from unstructured clinical interviews, not the criteria themselves: structured interviews like the ADIS-5 rebound reliability into the 'good' to 'excellent' range. GAD requires excessive worry more days than not for 6+ months with 3+ of 6 symptoms (adults) or 1+ symptom (children). The 6-month criterion helps distinguish persistent GAD from transient stress reactions.

Question 3

What's the 6-month duration criterion for, and does it actually help distinguish GAD from transient stress?

Accepted Answer

GAD achieved an intraclass kappa of just 0.20 in the DSM-5 field trials — two clinicians agreed only 20% more often than chance. The unreliability stems from unstructured clinical interviews, not the criteria themselves: structured interviews like the ADIS-5 rebound reliability into the 'good' to 'excellent' range. GAD requires excessive worry more days than not for 6+ months with 3+ of 6 symptoms (adults) or 1+ symptom (children). The 6-month criterion helps distinguish persistent GAD from transient stress reactions.

Question 4

How many somatic symptoms are required and which ones are most common?

Accepted Answer

GAD achieved an intraclass kappa of just 0.20 in the DSM-5 field trials — two clinicians agreed only 20% more often than chance. The unreliability stems from unstructured clinical interviews, not the criteria themselves: structured interviews like the ADIS-5 rebound reliability into the 'good' to 'excellent' range. GAD requires excessive worry more days than not for 6+ months with 3+ of 6 symptoms (adults) or 1+ symptom (children). The 6-month criterion helps distinguish persistent GAD from transient stress reactions.

Question 5

Would a structured interview improve my diagnostic accuracy over clinical impression?

Accepted Answer

GAD achieved an intraclass kappa of just 0.20 in the DSM-5 field trials — two clinicians agreed only 20% more often than chance. The unreliability stems from unstructured clinical interviews, not the criteria themselves: structured interviews like the ADIS-5 rebound reliability into the 'good' to 'excellent' range. GAD requires excessive worry more days than not for 6+ months with 3+ of 6 symptoms (adults) or 1+ symptom (children). The 6-month criterion helps distinguish persistent GAD from transient stress reactions.

Question 6

What distinguishes sub-threshold worry from diagnosable GAD in practice?

Accepted Answer

GAD achieved an intraclass kappa of just 0.20 in the DSM-5 field trials — two clinicians agreed only 20% more often than chance. The unreliability stems from unstructured clinical interviews, not the criteria themselves: structured interviews like the ADIS-5 rebound reliability into the 'good' to 'excellent' range. GAD requires excessive worry more days than not for 6+ months with 3+ of 6 symptoms (adults) or 1+ symptom (children). The 6-month criterion helps distinguish persistent GAD from transient stress reactions.

PsychHQ

GAD Reliability: Why the Diagnosis Is Hard and What Helps