Validation of generalized anxiety disorder-2 as a screening tool for generalized anxiety disorder in the primary health care setting: study protocol

Mohammad J. M. A. Tamimi, Anna R. Sharif, Saad T. Sedeeq, Ehab Hamed


Background: Anxiety screening in primary care is crucial for the identification and management of the condition. The generalized anxiety disorder-2 (GAD-2) is an abridged version of the tool composed of the first two questions of the GAD-7 for screening for anxiety in the general adult population in primary care settings. Patients who score more than 3 points are further evaluated for anxiety. Although there is a growing body of literature documenting the psychometric properties of the GAD-2 against a structured interview and the GAD-7, no earlier studies have assessed the performance of the GAD-2 in Qatar. This cross-sectional study primarily aims to examine the sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of GAD-2 scores for detecting anxiety among patients attending PHCC in Qatar.

Methods: The study will employ a periodic cross-sectional study of electronic medical record data of adult patients attending the primary health care settings between January of 2017 and December of 2019. The study population will include all adult population with documented GAD-7 scores. We will exclude all patients with other mental health diagnoses, including mental disability, schizophrenia, and dementia.

Conclusions: GAD-2 questionnaire forms an easy to administer screening tool. The cut-off value in various international settings is set at a score of equal to or more than 3. The study will report on the diagnostic properties of GAD-2 scores against the documented diagnosis of anxiety by health care professionals. The result helps to tailor the cut-off value to its local settings.

Trial Registration: Trial registration number is PHCCDCR202003019.


Generalized anxiety disorder, Psychometric properties, Health care professionals

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