The Generalized Anxiety Disorder 7-item scale (GAD-7) is a widely used self-administered diagnostic tool designed to screen for and assess the severity of generalized anxiety disorder (GAD).[1] Comprising seven items, the GAD-7 measures the frequency of anxiety symptoms over the past two weeks, with respondents rating each item on a scale from "not at all" to "nearly every day." Developed by Dr. Robert L. Spitzer and colleagues,[1] the GAD-7 is commonly used in both clinical settings and research to identify GAD and to monitor treatment outcomes. It is valued for its simplicity, reliability, and validity in detecting anxiety symptoms in diverse populations.
The GAD-7 is normally used in outpatient and primary care settings for referral to a psychiatrist pending outcome.[2] A systematic review compared screening tools and concluded that the GAD-7 is the most efficient one for identifying GAD as well as panic disorders in primary care populations.[3]
Criteria
The GAD-7 has seven items, which measure severity of various signs of GAD according to reported response categories with assigned points.[2] The GAD-7 items include:
Response options range from “not at all” (= 0 points), “several days” (= 1 point), “more than half the days” (= 2 points), and “nearly every day” (= 3 points) with a score range from 0-21 points.[1]
Interpretation of results
The assessment is indicated by the total score, which is made up by adding together the scores for the scale of all seven items with responses getting 0 to 3 points:
The normative data enable users of the GAD-7 to discern whether an individual's anxiety score is normal, or mildly, moderately, or severely elevated.[6] However, while the GAD-7 seem to be able to provide probable cases of GAD, it cannot be used as replacement for clinical assessment and additional evaluation should be used to confirm a diagnosis of GAD.[1][7]
Score
Risk Level
Suggested Intervention
0-4
No to Low risk
None
5-9
Mild
Repeat on follow-up
10-14
Moderate
Further evaluation required. Consider adjusting treatment plan.
15+
Severe
Adjust treatment plan. Higher level of care needed. Pharmacology re-evaluation.
Reliability and validity
The GAD-7 was originally validated in a primary care sample and a cutoff score of 10 (which the authors considered optimal) had a sensitivity value of 0.89 and a specificity value of 0.82 for identifying GAD. The authors of the questionnaire also found acceptable sensitivity and specificity values when the questionnaire was used as a general screen to identify other anxiety disorders (Panic Disorder, Social Anxiety, and PTSD) (GAD-7, score ≥ 8: sensitivity: 0.77, specificity: 0.82).[8]
The GAD-7 has further been studied and validated in numerous other samples and settings. [9] It has been shown to correlate with other measures of anxiety and has been considered superior to other questionnaires. [10][11][12] The GAD-7 has been evaluated in samples of both children and young individuals [13] as well as older adults. [14] It has been used in more than 2500 peer reviewed publications indexed in PubMed (current search here). The consensus is that it can efficient tool for screening for GAD and assessing its severity in clinical practice and research.[15] A meta-analysis found that it achieved acceptable accuracy at a cutoff point of 8 (sensitivity of 0.83, specificity: 0.84, pooling 12 samples and 5223 participants).[16]
The use of sumscores (i.e. summing the scores of each item) is supported by psychometric studies in some contexts, but using techniques based on factor analysis are deemed more precise.[17]
^ abLöwe B, Decker O, Müller S, Brähler E, Schellberg D, Herzog W, et al. (March 2008). "Validation and standardization of the Generalized Anxiety Disorder Screener (GAD-7) in the general population". Medical Care. 46 (3): 266–274. doi:10.1097/mlr.0b013e318160d093. PMID18388841. S2CID16052239.
^Herr NR, Williams JW, Benjamin S, McDuffie J (July 2014). "Does this patient have generalized anxiety or panic disorder?: The Rational Clinical Examination systematic review". JAMA. 312 (1): 78–84. doi:10.1001/jama.2014.5950. PMID25058220.
^Swinson RP (December 2006). "The GAD-7 scale was accurate for diagnosing generalised anxiety disorder". Evidence-Based Medicine. 11 (6): 184. doi:10.1136/ebm.11.6.184. PMID17213178. S2CID42283551.
^Löwe B, Decker O, Müller S, Brähler E, Schellberg D, Herzog W, et al. (March 2008). "Validation and standardization of the Generalized Anxiety Disorder Screener (GAD-7) in the general population". Medical Care. 46 (3): 266–274. doi:10.1097/MLR.0b013e318160d093. JSTOR40221654. PMID18388841. S2CID16052239.
^Plummer F, Manea L, Trepel D, McMillan D (2016-03-01). "Screening for anxiety disorders with the GAD-7 and GAD-2: a systematic review and diagnostic metaanalysis". General Hospital Psychiatry. 39: 24–31. doi:10.1016/j.genhosppsych.2015.11.005. PMID26719105.
^Kroenke K, Spitzer RL, Williams JB, Löwe B (2010-07-01). "The Patient Health Questionnaire Somatic, Anxiety, and Depressive Symptom Scales: a systematic review". General Hospital Psychiatry. 32 (4): 345–359. doi:10.1016/j.genhosppsych.2010.03.006. PMID20633738.
^Dear BF, Titov N, Sunderland M, McMillan D, Anderson T, Lorian C, et al. (September 2011). "Psychometric comparison of the generalized anxiety disorder scale-7 and the Penn State Worry Questionnaire for measuring response during treatment of generalised anxiety disorder". Cognitive Behaviour Therapy. 40 (3): 216–227. doi:10.1080/16506073.2011.582138. PMID21770844.
^Guzick A, Storch EA, Smárason O, Minhajuddin A, Drummond K, Riddle D, et al. (February 2024). "Psychometric properties of the GAD-7 and PROMIS-Anxiety-4a among youth with depression and suicidality: Results from the Texas youth depression and suicide research network". Journal of Psychiatric Research. 170: 237–244. doi:10.1016/j.jpsychires.2023.12.033. PMID38169247.
^Wild B, Eckl A, Herzog W, Niehoff D, Lechner S, Maatouk I, et al. (October 2014). "Assessing generalized anxiety disorder in elderly people using the GAD-7 and GAD-2 scales: results of a validation study". The American Journal of Geriatric Psychiatry. 22 (10): 1029–1038. doi:10.1016/j.jagp.2013.01.076. PMID23768681.
^Plummer F, Manea L, Trepel D, McMillan D (2016). "Screening for anxiety disorders with the GAD-7 and GAD-2: a systematic review and diagnostic metaanalysis". General Hospital Psychiatry. 39: 24–31. doi:10.1016/j.genhosppsych.2015.11.005. PMID26719105.