An evaluation of the Acsádi-Nemeskéri Complex Method for adult age estimation on a black South african sample

Abstract

The Acsádi and Nemeskéri Complex Method is a multifactorial method that utilises four skeletal indicators and a weighting system to assess adult skeletal age. It uses four skeletal indicators, including pubic symphysis, endocranial sutures, and internal structural changes in the proximal femur and humerus. The Complex Method has been criticized for its small sample size, statistical validity, and constant under- and overestimation of age for older and younger individuals, respectively. This study tested the Complex Method's performance on a black South African sample (n = 103), and Bayesian statistics was employed to see whether a more statistically robust approach would improve accuracy. Results somewhat support the criticism of the Complex Method’s tendency to under- and overestimate age. In contrast to Acsádi and Nemeskéri's findings, combinations utilising two or three skeletal indicators generally outperformed combinations using all four skeletal indicators. Given the method’s poor performance, population- and sex-specific skeletal indicator combinations and weighting systems must be developed before future use in this sample. Bayesian statistics provided some improvements, decreasing over- and underestimations, especially in males. Some benefits of using the weighting system were observed, as the Complex Method outperformed the Bayesian Method in females. Bayesian statistics in age estimation has some merit but requires large sample sizes with a good spread of age-related changes.