Abstract Background Care experienced children and young people (CECYP) are at risk of mental health difficulties. This review aimed to examine the impact of placement instability on the mental health outcomes of CECYP and to explore how placement instability is measured. Methods This review was conducted following the PRISMA guidance. Four databases (PsycINFO, Embase, Medline and ProQuest) were initially searched on 14 th December 2023, with an updated search conducted on January 29 th 2025. The following inclusion criteria were used: quantitative observational studies, CECYP (0–18 years), mental health difficulties as the outcome and placement instability as the exposure. The quality of the included studies was also assessed. The results from all papers included in the review were narratively synthesised and results from a subsample of the papers eligible for quantitative synthesis were analysed using a random effects meta‐analysis to examine the association between placement instability and mental health outcomes of CECYP. Results Twenty‐two studies were eligible for inclusion. The measurement of placement instability varied with some studies counting number of placement moves and some grouping number of moves into levels. The time frames in which moves were measured also varied. Overall, placement instability had a negative impact on mental health outcomes in CECYP, irrespective of age, sex, domain of mental health assessed (internalising and externalising), and initial levels of mental health. The meta‐analysis found that placement instability had a small significant association with both internalising ( r = 0.14, 95% CI = 0.12, 0.17) and externalising ( r = 0.14, 95% CI = 0.11, 0.18) mental health difficulties. Conclusion Placement instability is inconsistently measured and defined in the literature. Despite this heterogeneity in operationalisation, it remains a concerning risk factor for mental health difficulties of CECYP. Efforts should be made to minimise instability for this population. Trial Registration The protocol was registered on PROSPERO on the 2nd of February 2024 (CRD42024444031), can be found at https://www.crd.york.ac.uk/PROSPERO/view/CRD42024444031 .
Sparks et al. (Sat,) studied this question.