Reliability of the Schmeling method for bone age estimation using the clavicle: Systematic review and meta-analysis

Area of Science:

• Forensic Anthropology
• Radiology
• Skeletal Biology

Background:

• Clavicular ossification is crucial for forensic age estimation in late adolescence and early adulthood.
• The reliability of the Schmeling method with conventional radiography (CR) requires further evaluation.

Purpose of the Study:

• To systematically review and meta-analyze the applicability of the Schmeling method using CR for forensic age estimation.
• To assess the reliability and limitations of this method in diverse study populations.

Main Methods:

• Systematic literature search across multiple databases (Embase, LILACS, PubMed/MEDLINE, SciELO, Scopus, Web of Science).
• Inclusion of studies using the Schmeling method on CR for medial clavicular ossification.
• Meta-analysis of mean ages per ossification stage, with heterogeneity assessment (Cochran's Q, I²).
• Risk of bias assessment using the Joanna Briggs Institute checklist.

Main Results:

• Nine studies were included; five were eligible for meta-analysis.
• Mean age increased progressively across ossification stages.
• Substantial inter-study heterogeneity (I² ≥ 79.4%) was observed, particularly in advanced stages.
• Sensitivity analyses confirmed persistent heterogeneity, indicating wide prediction intervals.

Conclusions:

• The Schmeling method on CR reflects general skeletal maturation patterns but is limited by significant inter-study heterogeneity.
• The method's reliability for forensic age estimation is compromised, and it should not be used in isolation.
• Methodological standardization and consistent reporting are needed to enhance its forensic applicability.