Gender and other diversity-related factors in psychiatric hospital care: protocol for the participatory mixed-methods PSY-DIVER study

Background: Psychiatric hospital care is multimodal and typically comprises pharmacotherapy, psychotherapy, social therapy, occupational therapy, exercise therapy, and various forms of creative therapies. The use, acceptance and effectiveness of these interventions may be shaped by gender and further diversity-related factors including age, migration background, sexual orientation, religious beliefs and socioeconomic status. The impact of such diversity-related factors on psychiatric inpatient care processes and outcomes has not been comprehensively examined in German psychiatric hospitals. Methods: PSY-DIVER is a participatory mixed-methods research project conducted by the LVR Institute for Research and Education. The project runs from 1 November 2025 to 31 October 2028 and comprises four linked components: participatory project governance including a co-creation workshop, clinical routine data analyses, qualitative interviews followed by quantitative online surveys, and a two-round Delphi process to develop recommendations for clinical practice. In the routine data component, routine data from the nine psychiatric LVR hospitals with approximately 500,000 inpatient and day-care clinic cases and 1.7 million outpatient cases from 2015 to 2024 will be analysed, with a planned extension to more recent retrospective data during the project period. Structured routine data will be enriched by automated extraction of additional diversity-related variables from clinical free text using a rule-based natural language processing pipeline and locally hosted large language models in a secure local environment. Primary data collection will include 31 semi-structured interviews with mental health service users, relatives, and professionals, as well as online surveys with approximately 300 service users, 100 relatives, and 100 professionals. Integrated findings from these project parts will inform a structured consensus process with approximately 40 professional experts and experts by experience to formulate recommendations for a more diversity-sensitive psychiatric hospital care. Discussion: PSY-DIVER is designed to generate a detailed empirical account of how gender and other diversity-related factors are associated with treatment allocation, treatment processes and treatment outcomes in psychiatric hospital care. By combining large-scale routine data, primary stakeholder data and a participatory consensus process, the study aims to provide an evidence base for more equitable and diversity-sensitive psychiatric services.