Evidence-based milestone ages as a framework for developmental surveillance.

Developmental surveillance is the process of monitoring child development over time to promote healthy development and to identify possible problems. Standardized developmental screeners have greater sensitivity than milestone-based history taking. Unfortunately, Canadian screening guidelines, to date, are sparse, logistical barriers to implementation have slowed uptake of screening tests and physicians continue to rely on milestones. When using clinical impression as a framework for surveillance, clinicians may not know when to consider a milestone delayed because developmental attainments exist within an age range and there is an absence of referenced percentiles on available published tables, which are particularly problematic for the cognitive and social-emotional sectors, which are less familiar to physicians. A novel, five-sector milestone framework with upper limits, referenced to the best available level of evidence, is presented. This framework may be used in teaching and may help physicians to better recognize failed milestones to facilitate early identification of children at risk for developmental disorders.