Assessing Virtual Anthropometric Measurements and Quantifying Their Relationship to Osteometric Measurements Using...

Anthropometrics are a powerful tool for understanding bodily diversity. Using computed tomography (CT) scans from the New Mexico Decedent Image Database, we assess sources of methodological error that may complicate virtual anthropometric methods and quantify the comparability of anthropometric and osteometric measures.

Standard measurement protocols were adapted for virtual measurement. Intra- and interobserver measurement error, and error from changing CT scan thresholds were evaluated. Relationships between anthropometric and osteometric correlates were then evaluated using pairwise Fligner-Killeen tests on coefficients of variation (CVs). Biological codependence was explored using reduced major axis (RMA) regressions.

Measurement and threshold errors were low. Breadth and circumferential measures had the largest measurement errors and were most impacted by different threshold choices. Linear measurements show no significant differences between anthropometric and osteometric definitions, while circumferential measures have significantly different CVs for the male (p = 0.02) and pooled groups (p = 0.01). Bi-iliocristal and bi-iliac breadths had significantly different CVs, except in the < 25 BMI group. RMA models reflect a positive linear relationship between paired measures that is stronger for linear (r ≥ 0.98) than circumferential (r = 0.82) measurements. Pelvic breadth shows the weakest relationship (r = 0.46).

Anthropometric measures can be precisely defined in a replicable manner in virtual spaces, and linear measurements taken osteologically are comparable to those taken anthropometrically. However, circumferential measures are more impacted by threshold choice and soft tissue variation than linear measurements. Anthropometrically and osteometrically defined circumferential correlates should be compared with caution. Pelvic breadth measurements may only be comparable in individuals with BMIs < 25.