Diagnostic Criteria for Generalized Anxiety Disorder
To diagnose Generalized Anxiety Disorder, the patient must exhibit excessive, uncontrollable worry about multiple life domains persisting for at least six months, accompanied by at least three of six associated symptoms (restlessness, fatigue, concentration difficulty, irritability, muscle tension, or sleep disturbance), causing clinically significant functional impairment. 1
Core Diagnostic Requirements
Excessive worry must be clearly excessive, difficult for the patient to control, and persist for at least six months across multiple topics—not just a single concern or stressor. 1, 2
The worry must be described by the patient as "uncontrollable" or difficult to control, distinguishing it from normal everyday worries. 1
The anxiety must involve multiple life domains (e.g., work, health, finances, relationships), not just one specific area. 1, 2
Required Associated Symptoms
At least three of the following six symptoms must be present (only one symptom required in children): 1
| Symptom | Description |
|---|---|
| Restlessness | Feeling keyed up or on edge [1] |
| Easy fatigue | Tiring easily [1] |
| Concentration difficulty | Difficulty concentrating or mind going blank [1] |
| Irritability | Increased irritability [1] |
| Muscle tension | Muscle tension or soreness [1] |
| Sleep disturbance | Difficulty falling/staying asleep or restless, unsatisfying sleep [1] |
Functional Impairment Requirement
The anxiety and worry must cause clinically significant distress or impairment in social, occupational, or other important areas of functioning. 1
Moderate GAD typically produces mild-to-moderate functional limitation (e.g., reduced work productivity, avoiding some social situations), while severe GAD markedly interferes with daily activities (e.g., inability to work, complete social withdrawal). 1
Document specific examples of functional impairment, such as missing work, avoiding social situations, or difficulty completing household tasks, to establish the threshold. 1
Exclusion Criteria
Before confirming GAD, systematically rule out alternative explanations:
Medical conditions that mimic anxiety must be excluded, including hyperthyroidism, hyperparathyroidism, cardiac arrhythmias, pheochromocytoma, hypoglycemia, hypoxia, chronic pain, diabetes, asthma, migraine, systemic lupus erythematosus, and lead intoxication. 1, 3
Substance-induced anxiety from alcohol, stimulants, caffeine, or withdrawal states must be identified and treated concurrently. 1
Medication-induced anxiety from corticosteroids, thyroid medications, analgesics, muscle relaxants, or interferon should be evaluated. 1, 3
Other anxiety disorders with more specific foci must be distinguished: panic disorder (discrete panic attacks), social anxiety disorder (fear of social scrutiny), specific phobias (circumscribed fears), and PTSD (trauma-related symptoms with intrusive re-experiencing and avoidance). 1
Adjustment disorder with anxiety requires a clear precipitating stressor and represents a psychological reaction rather than a direct physiological effect. 3
Screening Tools vs. Formal Diagnosis
GAD-7 Screening Instrument
The GAD-7 is the primary screening tool, assessing seven core anxiety symptoms over the past two weeks. 1
GAD-7 severity stratification and recommended actions: 1
| Score | Interpretation | Action |
|---|---|---|
| 0-4 | Minimal/no anxiety | Monitor only |
| 5-9 | Mild anxiety | Low-intensity interventions (education, self-help) |
| 10-14 | Moderate anxiety | Referral to psychology/psychiatry |
| 15-21 | Severe anxiety | Immediate specialist referral |
Critical distinction: A positive GAD-7 score (≥8–9) is a screening threshold, not a formal diagnosis. 1
Formal DSM diagnosis requires meeting the symptom count (≥3 of 6 associated symptoms), duration (≥6 months), and functional-impairment criteria, regardless of GAD-7 score. 1
Alternative Screening Tools
The GAD-2 (ultra-brief 2-item version) can be used for initial screening, with a cutoff score of ≥3 indicating need for further assessment. 2
The GAD-Q-IV (9-item self-report) and Penn State Worry Questionnaire (PSWQ) (16-item scale) are validated alternatives for assessing DSM criteria and worry severity. 1
Comorbidity Assessment
Major depressive disorder co-occurs in approximately 31% of GAD cases; screen with PHQ-9 or direct questioning about depressed mood, anhedonia, and other depressive symptoms. 1
Alcohol or substance use disorders frequently complicate anxiety and must be treated concurrently. 1
Other anxiety disorders (panic disorder, social anxiety, specific phobias) commonly co-occur and require systematic assessment. 1, 3
Risk Factors to Document
Prior anxiety disorder diagnoses increase the likelihood of current GAD. 1
Family history of anxiety or mood disorders. 1
Chronic medical illnesses raise GAD risk. 1
Major life stressors should be documented to distinguish GAD from adjustment disorder. 1
Cultural Considerations
Non-Western populations more commonly present with somatic symptoms (fatigue, muscle tension, palpitations, dizziness, indigestion) rather than psychological symptoms. 1
Conduct evaluation in the patient's preferred language using interpreter services when needed; lack of linguistic support has been linked to misdiagnosis. 3
Assess whether somatic symptoms dominate and whether the patient's cultural background emphasizes physical over psychological expression of distress. 3
Common Diagnostic Pitfalls
Do not conflate screening cut-offs with diagnostic criteria—a positive GAD-7 prompts evaluation but does not establish diagnosis. 1
Do not miss comorbid depression—systematically screen all GAD patients for depressive symptoms. 1
Do not overlook substance use disorders—they require concurrent treatment and complicate anxiety management. 1
Do not misclassify proportionate anxiety as pathological—anxiety must be excessive relative to the actual threat or situation. 3
Do not ignore cultural variations—somatic presentations are common and valid expressions of GAD in many cultures. 1, 3
Vague terms like "marked," "excessive," and "out of proportion" rely heavily on clinician judgment; use concrete functional examples to establish thresholds. 3