The predictive value of universal preschool developmental assessment in identifying children with later educational difficulties: A systematic review
Authors: Cairney David G. , Kazmi Aun , Delahunty Lauren , Marryat Louise , Wood Rachael 
Published: March 2021

Background
Developmental delay affects substantial proportions of children. It can generally be identified in the pre-school years and can impact on children’s educational outcomes, which in turn may affect outcomes across the life span. High income countries increasingly assess children for developmental delay in the early years, as part of universal child health programmes, however there is little evidence as to which measures best predict later educational outcomes. This systematic review aims to assess results from the current literature on which measures hold the best predictive value, in order to inform the developmental surveillance aspects of universal child health programmes.

Methods
Systematic review sources: Medline (2000 –current), Embase (2000 –current), PsycInfo (2000 –current) and ERIC (2000 –current). Additional searching of birth cohort studies was undertaken and experts consulted.
Eligibility criteria: Included studies were in English from peer reviewed papers or books looking at developmental assessment of preschool children as part of universal child health surveillance programmes or birth cohort studies, with linked results of later educational success/difficulties. The study populations were limited to general populations of children aged 0–5 years in high income countries.
Study selection, data extraction and risk of bias assessment were carried out by two independent authors and any disagreement discussed. PROSPERO registration number CRD42018103111.

Results
Thirteen studies were identified for inclusion in the review. The studies were highly heterogeneous: age of children at first assessment ranged from 1–5 years, and at follow-up from 4–26 years. Type of initial and follow-up assessment also varied. Results indicated that, with the exception of one study, the most highly predictive initial assessments comprised combined measures of children’s developmental progress, such as a screening tool alongside teacher ratings and developmental histories. Other stand-alone measures also performed adequately, the best of these being the Ages and Stages Questionnaire (ASQ). Latency between measures, age of child at initial measurement, size of studies and quality of studies all impacted on the strength of results.

Conclusions
This review was the first to systematically assess the predictive value of preschool developmental assessment at a population level on later educational outcomes. Results demonstrated consistent associations between relatively poor early child development and later educational difficulties. In general, specificity and Negative Predictive Value are high, suggesting that young children who perform well in developmental assessment are unlikely to go on to develop educational difficulties, however the sensitivity and Positive Predictive Values were generally low, indicating that these assessments would not meet the requirements for a screening test. For surveillance purposes, however, findings suggested that combined measures provided the best results, although these are resource intensive and thus difficult to implement in universal child health programmes. Health service providers may therefore wish to consider using stand-alone measures, which also were shown to provide adequate predictive value, such as the ASQ.