The panic-agoraphobic spectrum comprises symptoms, traits, and behaviors considered to occur commonly in patients with panic disorder. DSM-IV criterion symptoms for panic disorder and agoraphobia are included, along with associated features found in the DSM-IV text and other symptoms, behavioral traits, and interpersonal behaviors that had been observed in the clinical practice and research experience with mood disorders patients.

Panic-agoraphobic spectrum manifestations may occur even in the absence of threshold level criteria for panic disorder. Some are ''trait-like" symptoms that occur as the subtle manifestations of an illness diathesis. Early onset of such symptoms can act to shape developing mental functions and change the personality. Panic-agoraphobic spectrum features are also significant when they remain as residual symptoms or co-occur with another DSM-IV disorder. Failure to recognize and attend to residual or comorbid spectrum features in treating DSM-IV disorders may explain continued impairment, even when core Axis I symptoms have been successfully treated.

A cut-off of 35 on the total score was identified using ROC analysis to characterize individuals with significant levels of panic-agoraphobic spectrum symptoms. This score proved to be useful to discriminate patients with poorer response to treatment among those with mood disorders.

The structure of the instrument was analysed using a classical exploratory factor analysis based on a tetrachoric correlation matrix and oblique rotation. 10 factors were extracted, accounting overall for 66.3% of the variance of the questionnaire: panic symptoms, agoraphobia, claustrophobia, separation anxiety, fear of losing control, drug sensitivity and phobia, medical reassurance, rescue object, loss sensitivity, reassurance from family members. The first two factors comprise the DSM-IV criteria for panic disorder and agoraphobia. The algorithm for calculating the scores of the factors is listed below.

Scoring

Each of the PAS instruments consists of 114 items coded as present or absent through the subject’s lifetime or over the past week or month and collapsed into eight domains.
See algorithm section, below on this page for how to score the instrument.

Psychometric Properties

Cassano GB, Banti S, Mauri M, Dell’Osso L, Miniati M, Maser JD, Shear MK, Frank E, Grochocinski V, Rucci P: Internal consistency and discriminant validity of the Structured Clinical Interview for Panic-Agoraphobic Spectrum (SCI-PAS). Int J Meth Psych Res 8:138-145, 1999.

Shear MK, Rucci P, Grochocinski VJ, Vanderbilt J, Houck P: Reliability and validity of the panic disorder severity scale: Replication and extension. J Psych Res 35:293-6, 2001.

Rucci P, Miniati M, Oppo A, Mula M, Calugi S, Frank E, Shear MK, Mauri M, Pini S, Cassano GB.: The structure of lifetime panic-agoraphobic spectrum. J Psychiatr Res. 2009 Jan;43(4):366-79.

general scores

Note: each items is scored as "0" (NO), "1" (YES).
(1) separation sensitivity	sum of items 1-15
(2) panic-like symptoms	sum of items 16-42
(3) stress sensitivity	sum of items 43-44
(4) substance and medication sensitivity	sum of items 45-53
(5) anxious expectation	sum of items 54-58
(6) agarophobia	sum of items 59-83
(7)illness related phobias and hypochondriasis	sum of items 84-88
(8) reassurance orientation	sum of items 89-114
Total score (sum of domains scores) range 0 - 114 Threshold for total score: 35

factor scores: sum of items for each factor

Factors	Description	Items
Panic symptoms (range 1-18)	DSM-IV criteria for panic attacks as heart pounding, racing, skipping, trembling or shaking	7, 16, 17, 18, 19, 20, 21, 22, 23, 27, 28, 29, 32, 33, 36, 42, 43, 57
Agoraphobia (range 1-18)	Feeling nervous when in a crowded place or in an open place like a town square or a wide street	39, 59, 60, 61, 63, 64, 65, 66, 67, 68, 69, 70, 72, 83, 98, 99, 100, 101
Claustrophobia (range 1-15)	Feelings of restriction or entrapment	34, 41, 62, 71, 74, 75, 76, 77, 78, 79, 80, 81, 88, 106, 110
Separation anxiety (range 1-12)	Anxiety symptoms associated with separation from loved ones or from home	1, 2, 3, 5, 4, 6, 8, 9, 10, 37, 97, 111
Fear of losing control (range 1-11)	Fear of losing one's mind or losing control, feeling confused or numb, symptoms of depersonalization and derealisation	24, 25, 26, 30, 31, 35, 40, 47, 56, 58, 85
Drug sensitivity and phobia (range 1-11)	Excessive worrying about the possible side effects of medication	48, 49, 50, 51, 52, 53, 54, 55, 84, 86, 87
Medical reassurance (range 1-8)	Need for reassurance from professionals	92, 93, 94, 95, 96, 112, 113, 114
Rescue object (range 1-5)	Need to take objects with them such as an umbrella, a hat or a bottle of water to reduce anxiety	102, 103, 104, 105, 107
Loss sensitivity (range 1-4)	Having more difficulty than the average person in adjusting to the end of a relationship with a friend or a lover or the end of a psychotherapy	11, 12, 13, 15
Family reassurance (range 1-3)	Need for reassurance from family members or friends	89, 90, 91