Is Binary Grading Better Than WHO System for Grading Epithelial Dysplasia? A Systematic Review and Meta-Analysis

Area of Science:

• Pathology
• Medical Diagnostics
• Histopathology

Background:

• Epithelial dysplasia (ED) assessment relies on grading systems.
• The World Health Organization (WHO) and binary systems are commonly used.
• Variability in ED grading impacts patient management.

Purpose of the Study:

• To systematically evaluate and compare the intra- and inter-observer agreement of WHO and binary grading systems for ED.
• To synthesize existing evidence through meta-analysis.

Main Methods:

• A systematic literature search was performed across Medline, Scopus, and EBSCOhost.
• Observational studies comparing WHO and binary ED grading agreement were included.
• Meta-analysis utilized kappa (κ) values and standard errors (SE) for pooled estimations.

Main Results:

• The binary system showed significantly better inter-observer agreement (κ = 0.31) than the WHO system (κ = 0.14).
• Intra-observer agreement was also higher for the binary system (κ = 0.44) compared to the WHO system (κ = 0.25).
• Analysis included data from 46 pathologists across eight studies.

Conclusions:

• The binary grading system offers improved intra-observer and inter-observer agreement for ED assessment over the WHO system.
• Current evidence suggests the binary system's superiority, but larger cohort studies are required for definitive clinical conclusions.