Psychometric analysis of the Swedish panic disorder severity scale and its self-report version. (2nd January 2019)

• Record Type: Journal Article
• Authors: Svensson, Martin; Nilsson, Thomas; Johansson, Håkan; Viborg, Gardar; Perrin, Sean; Sandell, Rolf
• Is Part Of: Nordic journal of psychiatry. Volume 73:Number 1(2019)
• Page Start: 58
• Page End: 63
• Publication Date: 2019-01-02
• Subjects: Panic disorder -- assessment -- anxiety -- psychometric properties -- factor analysis; Psychopharmacology -- Periodicals; Psychotherapy -- Periodicals; Psychiatry -- Periodicals; Psychiatry -- Scandinavia -- Periodicals; 616.89
• DOI: 10.1080/08039488.2018.1554699
• Languages: English
• ISSNs: 0803-9488

Abstract

Abstract: Background: Panic disorder, with or without agoraphobia (PDA or PD, respectively), is a major public health problem. After having established a PD diagnosis based on the DSM or the ICD systems, the Panic Disorder Severity Scale (PDSS) is the most widely used interview-based instrument for assessing disorder severity. There is also a self-report version of the instrument (PDSS-SR); both exist in a Swedish translation but their psychometric properties remain untested. Methods: We studied 221 patients with PD/PDA recruited to a randomized controlled preference trial of cognitive-behavioral and brief panic-focused psychodynamic psychotherapy. In addition to PDSS and PDSS-SR the participants completed self-reports including the Clinical Outcome in Routine Evaluation – Outcome Measure, Montgomery Åsberg Depression Rating Scale, Sheehan Disability Scale, Bodily Sensations Questionnaire and the Mobility Inventory for Agoraphobia. Results: PDSS and PDSS-SR possessed excellent psychometric properties (internal consistency, test–retest reliability) and convergent validity. A single factor structure for both versions was not confirmed. In terms of clinical utility, the PDSS had very high inter-rater reliability and correspondence with PD assessed via structured diagnostic interview. Both versions were sensitive to the effects of PD-focused treatment, although subjects scored systematically lower on the self-report version. Conclusions: The study confirmed the reliability and validity of the Swedish versions of PDSS and PDSS-SR. Both versions were highly sensitive to the effects of two PD-focused treatments and can be used both in clinical and research settings. However, further investigation of the factor structures of both the PDSS and PDSS-SR is warranted. Trial registration: ClinicalTrials.gov identifier: NCT01606592.