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<div><p>The objective of this scoping review is to investigate psychological interventions developed, evaluated, and considered for patients with delirium in intensive care units (ICU). Data will be extracted from sources of evidence that address interventions for delirium-related distress and/or cognitive impairments in the adult ICU population, suitable for delivery by or under the supervision of a psychological practitioner. ICU delirium is a common and impactful condition that adversely affects patient outcomes, including prolonged hospitalisation and deteriorating mental health. Despite its significance, it remains poorly understood. Addressing the psychological impact of delirium is crucial for improving both short- and long-term psychological outcomes in ICU patients. However, current non-pharmacological interventions often fail to consider this issue. The inclusion criteria encompass psychological interventions for critically ill adults that directly impact their thoughts, feelings, behaviour and/or cognition. Additionally, interventions involving relatives and multi-component non-pharmacological approaches will be considered. The databases Medline (Ovid), PsycINFO (Ovid), Embase (Ovid), and CINAHL Plus will be searched, covering literature from 1990 to the present. We chose 1990 as the earliest time point for searches because psychological input in ICUs began globally around 2000, with notable expansion in the past decade. Reference lists from identified articles will be hand-searched and PsycEXTRA (Ovid) and <a href="http://WorldCat.org" target="_blank">WorldCat.org</a> will be searched for grey literature. Relevant information will be extracted and reported using a PRISMA flow diagram, characteristics and frequency table as well as narrative descriptions. This review aims to collate evidence to guide the development and evaluation of new psychological interventions to address delirium in the ICU.</p></div>