Which psychotherapy is effective in panic disorder? And which delivery formats are supported by the evidence? Study protocol for two systematic reviews and network meta-analyses

Introduction: Panic disorder is among the most prevalent anxiety diseases. Although psychotherapy is recommended as first-line treatment for panic disorder, little is known about the relative efficacy of different types of psychotherapies. Moreover, there is little evidence concerning the effectiveness of different formats of major psychotherapeutic types, such as cognitive-behavioural therapy (CBT). In this protocol, we present an overarching project consisting of two systematic reviews and network meta-analyses (NMA) to shed light on which psychotherapy (NMA-1), and specifically, which CBT delivery format (NMA-2) should be considered most effective for adults suffering from panic disorder with or without agoraphobia.

Methods and analyses: Starting from a common pool of data, we will conduct two systematic reviews and NMA of randomised controlled trials examining panic disorder. A comprehensive search will be performed in electronic databases MEDLINE, Embase, PsycINFO and the Cochrane Register of Controlled Trials-CENTRAL from database inception to 1 January 2021 to identify relevant studies. A systematic approach to searching, screening, reviewing and data extraction will be applied. Titles, abstract and-whenever necessary-full texts will be examined independently by at least two reviewers. The quality of the included studies will be assessed using the revised Cochrane risk of bias tool V.2. The primary efficacy outcome will be anxiety symptoms at study endpoint. The primary acceptability outcome will be all-cause discontinuation, as measured by the proportion of patients who had discontinued treatment for any reason at endpoint. Data will be pooled using a random-effects model. Pairwise and NMA will be conducted.

Ethics and dissemination: No ethical approval is necessary for these two studies, as there will be no collection of primary data. The results will be disseminated through peer-reviewed publications and presentations at national and international conferences and meetings.