Study to Assess the Variables that Influence the Degree of Mummification and Skeletonization in a modern USA Population

Abstract

Taphonomic studies through experimental research at Forensic Anthropological Research Facilities are continuously developing our understanding of soft tissue decomposition in controlled environments. Photographic archives provide an alternative means to study decomposition using associated detailed case notes, environmental variables surrounding the death and (if known) post-mortem interval (PMI). Leccia, Alunni and Quatrehomme (2018) utilized this resource to calculate the total body surface area (TBSA) in bodies with extensive and complete mummification using “the rule of nines,” a method where the body is sectioned into nine anatomical sections to assess TBSA burnt however they did not test this statistically. This article aims to revise their study by implementing the more representative Lund and Browder chart (Yasti et al. 2015) to visually assess all degree of mummification and skeletonization, through a secondary data analysis study using autopsy photographs of 17 cases from Allegheny County Medical Examiner’s Office, Pittsburgh, between 2007–2016. Principal component analysis (PCA) was conducted on the body section scores to reveal high correlation co-efficients (>0.95) between anatomical sections indicating a high confidence, mummification and/or skeletonization on multiple body parts will co-exist on a decomposed body. PCA of recorded variables revealed that after body position was removed from analysis, the majority of variables had strong values. i.e., those with a numerically large magnitude (.750 to .850, -.767 to -.840). Multiple regression analysis and ANOVA revealed age to be the significant independent variable at 10% significance level. The results of this study have forensic application for crime scene investigators, mummification and skeletonization percentages can be effectively recorded upon examination of a body, whilst also demonstrating variables that have a significant effect on presentation of these two post-mortem changes. Further examination of globally dependant variables affecting modern mummification is encouraged.