The Generalized Anxiety Disorder 7-item (GAD-7) is an easy to perform initial screening tool for generalized anxiety disorder (Spitzer 2006).
Scores ≥10: Further assessment (including diagnostic interview and mental status examination) and/or referral to a mental health professional recommended.
This tool should be used for screening and monitoring symptom severity and cannot replace a clinical assessment and diagnosis.
Do not forget to rule out medical causes of anxiety before diagnosing an anxiety disorder (for example, EKG for arrhythmias, TSH for thyroid disease).
When screening for anxiety disorders, a score of 8 or greater represents a reasonable cut-point for identifying cases of generalized anxiety disorder; further diagnostic assessment is warranted to determine the presence and type of anxiety disorder. Using a cut-off of 8, the GAD-7 has a sensitivity of 92% and specificity of 76% for diagnosis generalized anxiety disorder (Plummer 2016; Kroenke 2007).
The following cut-offs correlate with level of anxiety severity:
| Score | Anxiety Severity | |
|---|---|---|
| 0-4 | Minimal Anxiety | |
| 5-9 | Mild Anxiety | |
| 10-14 | Moderate Anxiety | |
| ≥15 | Severe Anxiety |
Based on a recent meta-analysis, some experts have recommended considering using a cut-off of 8 in order to optimize sensitivity without compromising specificity (Plummer 2016).
Although designed as a screening tool for gneralized anxiety, the GAD-7 is also performs reasonably well as a screening tool for three other common anxiety disorders - Panic Disorder, Social Anxiety Disorder, and Posttraumatic Stress Disorder (Kroenke 2007) .
Performance of GAD-7 as Screening Tool for Anxiety Disorders
(Using GAD-7 Score Cut-off ≥10)
| Test | Sensitivity | Specificity | Positive Likelihood Ratio |
|---|---|---|---|
| Generalized Anxiety Disorder | 89% | 82% | 5.1 |
| Panic Disorder | 74% | 81% | 3.9 |
| Social Anxiety Disorder | 72% | 80% | 3.6 |
| Post-Traumatic Stress Disorder | 66% | 81% | 3.5 |
| Any anxiety disorder | 68% | 88% | 5.5 |
For all questions, answer with one of the following: Not at all = 0; Several days = +1; More than half the days = +2; Nearly every day = +3; The last question of the GAD-7 is a good indicator of patient's global impairment, though not included in the final calculation of points.
Initially validated in 2149 patients as a diagnostic tool for GAD (cutoff score 10-> sensitivity 89%, specificity 82%, test-retest reliability with ICC=0.83) (Spitzer 2006), the GAD-7 was later also found to have reasonable sensitivity and specificity as a screener for panic disorder, social phobia and PTSD (cutoff score 8- sensitivity 77%, specificity 82%; cutoff score 10 - sensitivity 68% and specificity 88% for any anxiety disorder)(Kroenke 2007).
The GAD-7 is useful in primary care and mental health settings as a screening tool and symptom severity measure for the four most common anxiety disorders (Generalized Anxiety Disorder, Panic Disorder, Social Phobia and PostTraumatic Stress Disorder). It is 70-90% sensitive and 80-90% specific across disorders / cutoffs. Higher GAD-7 scores correlate with disability and functional impairment (in measures such as work productivity and health care utilization) (Spitzer 2006; Ruiz 2011). The last item “How difficult have these problems made it for you to do your work, take care of things at home, or get along with other people?” - although not used in the calculation - is a good indicator of the patient’s global impairment and can be used to track treatment response..
Over the last two weeks, how often have you been bothered by the following problems?