This is calculated by assigning scores of 0‚ 1‚ 2‚ and 3‚ to the response categories of “not at all‚” “several days‚” “more than half the days‚” and “nearly every day‚” respectively. GAD-7 total score for the seven items ranges from 0 to 21. Scores of 5‚ 10‚ and 15 represent cut points for mild‚ moderate‚ and severe anxiety‚ respectively. Though designed primarily as a screening and severity measure for generalized anxiety disorder‚ the GAD-7 also has moderately good operating characteristics for three other common anxiety disorders – panic disorder‚ social anxiety disorder‚ and post-traumatic stress disorder. When screening for individual or any anxiety disorder‚ a recommended cutpoint for further evaluation is a score of 10 or greater.
References
Spitzer RL‚ Kroenke K‚ Williams JBW‚ for the Patient Health Questionnaire Primary Care Study Group. Validation and utility of a self-report version of PRIME-MD: the PHQ Primary Care Study. JAMA 1999;282:1737-1744.
Spitzer RL‚ Williams JBW‚ Kroenke K‚ et al. Validity and utility of the Patient Health Questionnaire in assessment of 3000 obstetrics-gynecologic patients. Am J Obstet Gynecol 2000; 183:759-769
Spitzer RL‚ Kroenke K‚ Williams JBW‚ Löwe B. A brief measure for assessing generalized anxiety disorder: the GAD-7. Arch Intern Med 2006;166:1092-1097.
Kroenke K‚ Spitzer RL‚ Williams JBW. The PHQ-9: Validity of a brief depression severity measure. J Gen Intern Med 2001;16:606-613.
Kroenke K‚ Spitzer RL‚ Williams JBW. The PHQ-15: Validity of a new measure for evaluating somatic symptom severity. Psychosom Med 2002;64:258-266.
Kroenke K‚ Spitzer RL. The PHQ-9: a new depression diagnostic and severity measure. Psychiatric Annals 2002;32:509-521. [also includes validation data on PHQ-8]
Kroenke K‚ Spitzer RL‚ Williams JBW. The Patient Health Questionnaire-2 : validity of a two-item depression screener. Med Care 2003; 41:1284-1292.
Kroenke K‚ Spitzer RL‚ Williams JBW‚ Monahan PO‚ Löwe B. Anxiety disorders in primary care: prevalence‚ impairment‚ comorbidity‚ and detection. Ann Intern Med 2007 (in press). [also includes additional validation data on GAD-7 and GAD-2]
Kroenke K‚ Spitzer RL‚ Williams JBW‚ Löwe B. An ultra-brief screening scale for anxiety and depression: the PHQ-4. Under review.
Löwe B‚ Kroenke K‚ Herzog W‚ Gräfe K. Measuring depression outcome with a short self-report instrument: sensitivity to change of the Patient Health Questionnaire (PHQ-9). J Affective Disorders 2004;78:131-140.
Löwe B‚ Unutzer J‚ Callahan CM‚ Perkins AJ‚ Kroenke K. Monitoring depression treatment outcomes with the Patient Health Questionnaire-9. Med Care 2004;42:1194-1201.