Systemic review of the relative age effect in Scottish schooling: a public health imperative for policy reform and equity.

Objectives: The relative age effect (RAE) is where an individual's age relative to their age-banded cohort influences various outcomes and has a globally observed pattern impacting health, academic performance and psychosocial development. Scotland's unique school commencement laws have resulted in extended schooling cohorts spanning up to 19 months, thus exacerbating RAE and subsequently widening health inequities. This research synthesises evidence to delineate the public health problem posed by RAE in the Scottish educational context and proposes evidence-based policy interventions. Design: A comprehensive policy brief methodology was employed, integrating a systematic literature review with extensive stakeholder engagement and detailed analysis of local data, including Scottish Government statistics. Data sources: Web of Science and EBSCOhost databases were searched, along with Scottish Government statistics. Eligibility criteria: Population, Intervention, Comparator, Outcome, Study Design frameworks and targeted search terms were used for study selection. Data extraction and synthesis: Ethical approval was obtained, and Sex and Gender Equity in Research and patient and public involvement considerations were integrated. Results: Analysis of Scottish data reveals increasing school entry deferral rates, particularly among children born in January and February. Furthermore, the trend appears to be influenced by government funding for additional childcare. This deferral appears to disproportionately favour white ethnic backgrounds, boys and higher socioeconomic strata, widening inequities. More so, RAE is associated with increased physical injury rates, adverse mental health outcomes (anxiety, depression, suicide), higher incidence of learning disabilities, diminished academic attainment and reduced psychosocial development (lower self-esteem and fewer leadership opportunities). Extended 19-month cohorts, such as the one offered in the Scottish education system, are predicted to amplify these disadvantages. Conclusions: The existence of extended 19-month schooling cohorts in Scotland represents a significant, yet under-recognised, public health issue. This structural anomaly perpetuates and exacerbates existing inequities in child development and well-being. A strategic realignment of default school entry with the legally stipulated age, complemented by multi-faceted RAE-mitigation strategies, offers a pragmatic, evidence-based and equitable pathway to improve holistic child health and developmental outcomes across the Scottish population.