FM	Foramen Magnum
OC	Occipital Condyle
OCL	Occipital Condyle Length
OCW	Occipital Condyle Width
OCT	Occipital Condyle Thickness
FML	Foramen Magnum Length
FMW	Foramen Magnum Width
SD	Sagittal Diameter
TD	Transverse Diameter
APD	Anteroposterior Diameter
ROC	Receiver Operating Characteristic
AQUA	Anatomical Quality Assurance Tool
PRISMA	Preferred Reporting Items for Systematic Reviews and Meta-Analyses
IOS	Influential Outlier Study
MD	Mean Difference
CI	Confidence Interval
SSE	Small Study Effect
I2	Higgins’ I-squared Statistic
CART	Classification and Regression Trees
meta-CART	Meta-analysis with Classification and Regression Trees