Estimation of sex from sternal dimensions derived from chest plate radiographs in contemporary Spaniards

A number of previous studies have demonstrated that osteometric analysis of the sternum provides a highly accurate method for discriminating adult sex in diverse population groups. In this study, sternal measurements were recorded from posteroanterior digital radiographs of the chest plate of 116 Spanish individuals (65 males and 51 females). Results demonstrated that all linear dimensions of the manubrium and mesosternum, sternal area, and sternal index were significantly sexually dimorphic in this population group. Discriminant function analyses incorporating several of these variables, individually or in combination, provided sex classification accuracy rates greater than 80.0 %, with associated sex biases below 5.0 %. A stepwise procedure, which can be used when a complete sternum is present, yielded the highest correct sex classification rate at 89.7 %. Only slightly lower allocation accuracy rates were obtained for multivariate equations which incorporated either dimensions of the manubrium or mesosternum (87.1 % for both formulae). Thus, the derived discriminant function equations should prove useful in forensic investigations, particularly those in which the pelvis or bones of the extremities are not available for analysis.