Univariate and multivariate methods for sexing the sacrum

Area of Science:

• Forensic Anthropology
• Bioarchaeology
• Human Osteology

Background:

• Accurate sex determination from skeletal remains is crucial in forensic anthropology.
• The sacrum, a key pelvic bone, offers potential for sex estimation.
• Conventional methods for sacral sex determination have varying degrees of accuracy.

Purpose of the Study:

• To evaluate the utility of conventional observations for sex determination from the sacrum.
• To identify specific metric traits and develop new indices for improved sex estimation.
• To compare the effectiveness of univariate and multivariate analyses across different racial groups.

Main Methods:

• Analysis of metric data from 200 sacra of known sex, age, and race.
• Univariate analysis focusing on significant sex differences in sacral measurements.
• Development and application of a novel index (S1 body to sacral breadth) and discriminant analysis.

Main Results:

• Significant sex differences in the sacrum are primarily located in the superior portion for both white and black individuals.
• Sacral curvature measurements are particularly important for sex differences in the black sample.
• The proposed S1 body to sacral breadth index demonstrated higher classification accuracy than other indices, especially in discriminant analysis for whites.

Conclusions:

• Conventional sacral measurements show sex-specific differences, with variations between racial groups.
• A new index relating S1 body to sacral breadth offers a more effective method for skeletal sex estimation.
• The choice between univariate and multivariate methods depends on bone condition and race, influencing sex determination accuracy.