The Argenta Classification for Positional Plagiocephaly in Infants: An Inter- and Intra-Rater Reliability Study

Positional plagiocephaly is a common condition in infants, characterized by asymmetrical posterior occipital flattening due to external mechanical pressure. The Argenta classification is an observational diagnostic tool that classifies plagiocephaly into five degrees of severity according to specific cranial asymmetry characteristics. The purpose was to examine the inter-rater and intra-rater reliability of the Argenta classification among developmental physiotherapists. Two raters examined 42 infants aged 6 weeks to 12 months that were separately enrolled in Clalit child development centers. A second observation was held within 7 days of the first observation. A strong agreement was reached among the raters (κ = 0.85, p < 0.0001) and within two observations of the same rater (κ = 0.90, p < 0.0001). The high degree of agreement indicates the high reliability of the Argenta classification. No significant relationships between severity and gender, age, flattened side, primaparity, number of pregnancies, type of birth, or the Alberta Infant Motor Scale score were found. In conclusion, the Argenta classification demonstrates high inter- and intra-rater reliability, particularly for milder severity levels. It is an easy, quick, and free method to use clinically without causing inconvenience to the assessed infant. While these results support clinical integration, particularly in resource-limited settings, the variable reliability across severity levels indicate that further validation studies are needed before universal adoption.