Access to treatment protocols and manuals for evidence-based psychological interventions for severe mental disorders: A survey of randomized trials included in network meta-analyses

Question Evidence-based psychological interventions for mental disorders are described in protocols and manuals, but are these resources accessible or publicly available? Study selection and analysis We surveyed randomized controlled trials (RCTs) from six large network meta-analyses of psychological interventions for severe mental disorders (psychotic, borderline personality, substance use, bipolar, anorexia and bulimia nervosa). Between January 2024 and February 2025, we retrieved protocols and manuals of psychological intervention arms using a multipronged approach (published protocol, trial registries, author contact, commercial availability). We report the proportion of trials and intervention arms for which protocols or manuals were (1) accessible, i.e., retrievable by any method, and (2) publicly versus commercially available. Findings We included 260 RCTs, with 422 active intervention arms. We retrieved published protocols for 20 RCTs (8%, 95% confidence interval/CI 5% to 12%) and contacted 450 authors for the remaining 240. Authors shared protocols for 43/240 trials (18%, 95% CI 13% to 23%), refused to share for 73 (30%, 95% CI 25% to 37%) and did not respond for 101 (42%, 95% CI 36% to 49%). Protocols or manuals were retrievable for 364 psychological intervention arms (86%, 95% CI 83% to 89%), with 191 available commercially (45%, 95% CI 40% to 50%) and 106 (25%, 95% CI 21% to 30%) publicly. Conclusions Retrieving detailed descriptions of psychological interventions used in trials, crucial for identifying treatment components, was challenging, resource-intensive and required multiple methods. Reliance on public availability and author sharing enabled access to about 40% of protocols or manuals. Funding European Union (European Research Council) Key messages What is already known on this topic Access to treatment protocols or manuals, which detail the component elements of psychological interventions and conditions of application, is paramount to evaluating these treatments. There is no previous systematic overview of the accessibility of protocols and manuals for mental disorders. What this study adds In a large-scale evaluation of 422 evidence-based psychological interventions for severe mental disorders, studied in 260 randomized trials, sourced from 6 large network meta-analyses, we could retrieve a detailed intervention description, operationalized as a protocol or manual, for about 86% of the active interventions. Around 45% of the protocols or manuals were only available commercially, and only around a quarter were publicly available. The retrieval rates are based on a resource-and time-intensive, multipronged approach, through searching multiple sources (papers, trials registries, Google for commercially available manuals) and extensive author contact. How this study might affect research, practice or policy Developing psychological treatments and evaluating these in randomized trials need to be complemented by a more streamlined and less taxing access to treatment components and other characteristics (e.g., delivery modes, training required), as for labels of approved drugs. To improve dissemination of effective psychological treatments - a global mental health priority, public availability of treatment manuals is crucial. Funders, journals, and trial registries could require sharing of intervention protocols.