Delirium can occur as a complication in approximately 34 % of critically ill children, including those admitted to the pediatric intensive care unit (PICU); it manifests as acute-onset changes in attention, cognition, and awareness (Semple et al., 2022). Delirium in the PICU can be categorized into hypoactive (46 %), hyperactive (45 %), and mixed (9 %) types, but the symptoms can fluctuate throughout the day (Martins and Fernandes, 2012, Traube et al., 2017). The well-known risk factors for delirium in the PICU include developmental delay, mechanical ventilation use, benzodiazepine use, anticholinergic use, younger age (<1 years old relative to 1–5, 6–12, and 13–21 years old), prolonged PICU stay, and use of physical restraints (Alvarez et al., 2018, Ista et al., 2023, Zhu et al., 2022). PICU delirium has been linked with prolonged length of mechanical ventilation, extended ICU stays, higher healthcare expenses, increased mortality rates, and reduced post-discharge quality of life. (Semple et al., 2022). Therefore, identifying delirium in critically ill children is crucial. However, identifying delirium can be challenging due to differences in age, development stage, and diagnosis (Flaigle et al., 2016) as well as difficulties in the feasibility of symptom evaluation according to the Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria (Smith et al., 2009). Thus, using a rapid and reliable assessment tool can help health-care professionals in the early and accurately identification of delirium in the PICU.

Four tools have been used for screening pediatric delirium in the clinical setting: the Pediatric Confusion Assessment Method for the intensive care unit (ICU, pCAM-ICU), Preschool Confusion Assessment Method for the ICU (psCAM-ICU), Pediatric Anesthesia Emergence Delirium (PAED), and Cornell Assessment of Pediatric Delirium (CAPD). The pCAM-ICU and psCAM-ICU are cognitively oriented interactive tools for children older than 5 years (Smith et al., 2011) and those aged 6 months to 5 years (Smith et al., 2016), respectively. Neither tool has been validated for use in children with developmental delays. The PAED is a reliable and simple tool for detecting emergency or hyperactive delirium, but not hypoactive delirium, in children older than 1 year (Sikich and Lerman, 2004). The CAPD is an observational tool for children of all ages and developmental abilities (Traube et al., 2012). All the tools were designed for bedside use, enabling rapid, real-time delirium screening in the PICU.

Although the CAPD, psCAM-ICU, and pCAM-ICU are recommended by the 2022 Society of Critical Care Medicine clinical practice guidelines in critically ill pediatric patients (Smith et al., 2022), no comparative study, thus far, has been conducted to assess the diagnostic accuracy of the pCAM-ICU, psCAM-ICU, PAED, and CAPD for screening delirium in the PICU. Furthermore, the present study examines the influence of study features and patient characteristics on the diagnostic accuracy, specifically focusing on the moderating effects of the four tools remain unclear. Given the clinical importance of such analyses, we conducted a comprehensive meta-analysis to pool and compare the diagnostic accuracy of the four tools for detecting delirium in the PICU.