Development of a brief diagnostic screen for panic disorder in primary care

Objective: The purpose of this study was to determine the utility of a brie f screening tool for panic disorder in the primary care setting. Methods: A total of 1476 primary care outpatients in three primary care medical clini cs on the West Coast of the United States were studied. Patients completed a brief self-report measure, the five-item Autonomic Nervous System questio nnaire (ANS), while in the waiting room. The presence of DSM-IV panic disor der was subsequently determined in groups of "screen-positive" and "screen- negative" subjects using the Composite International Diagnostic Interview. A subset of patients (N = 511) also completed the 21-item Beck Anxiety Inve ntory. Indices of diagnostic utility were calculated using receiving operat ing characteristic analyses to guide the selection of optimal cutoff levels . Results: The two-question version of the ANS had excellent sensitivity (r ange = 0.94-1.00 across the three clinic sites) and negative predictive val ue (0.94-1.00) but low specificity (0.25-0.59) and positive predictive valu e (range 0.18-0.40). The three- and five-question versions of the ANS had o nly modestly improved specificity, and this was achieved at the cost of red uced sensitivity and increased respondent burden to complete the questionna ire. The 21-item Beck Anxiety Inventory had maximal clinical utility at a c utoff level of greater than or equal to 20, but sensitivity was lower than desirable for a screening instrument (0.67). Conclusions: The two-question version of the ANS shows promise as a screening instrument for panic disord er in the primary care setting.