A field study to evaluate PMI estimation methods for advanced decomposition stages.

Area of Science:

• Forensic Pathology
• Decomposition Science
• Forensic Entomology

Background:

• Estimating postmortem interval (PMI) is crucial in forensic pathology but challenging, particularly in advanced decomposition stages.
• Current methods for PMI estimation, including rigor mortis, livor mortis, and algor mortis, become unreliable over time.
• Existing methods like forensic entomology, protein degradation analysis, and morphological scoring have limitations.

Purpose of the Study:

• To assess the practical application, interferences, and synergistic effects of various PMI estimation methods under field conditions.
• To evaluate the robustness of different decomposition assessment techniques against influencing factors.
• To establish a baseline for future research by identifying strengths and weaknesses of current PMI estimation tools.

Main Methods:

• A field study utilizing eight pig cadavers of varying weights and coverage decomposed under natural conditions for 16 days.
• Morphological changes were assessed using the total body score (TBS).
• Muscle samples were analyzed for protein degradation, and insect colonization was evaluated.

Main Results:

• The study identified the strengths and limitations of each tested PMI estimation method.
• Synergistic effects between methods were observed, suggesting potential for combined application.
• The robustness of methods varied depending on influencing factors like body weight and coverage.

Conclusions:

• No single method is universally applicable for all PMI estimations, especially in later stages.
• Combining multiple methods, such as morphological scoring, protein degradation analysis, and entomology, shows promise for improving PMI accuracy.
• Further research is needed to optimize combined methodologies for reliable forensic casework.