Methods Used to Estimate the Time of Death

Andrew Dani^*
*Correspondence: Andrew Dani, Department of Forensic Medicine, Óbuda University, Budapest, Hungary, Email:

Keywords

Forensic pathology • Post mortem interval • Machine learning

Introduction

At each death scene that is investigated, ambient and body temperatures are taken. Since 1839, this information has been utilised to estimate the time of death, an important consideration in situations of homicide and unnatural deaths. Common methods for estimating the time of death, the Glaister Equation and Henssge's nomogram, are unreliable and frequently disagree with one another. Thus, I wanted to assess them and make improvements. On the field, I gathered information and consistently recorded temperature readings. I also had access to published data and a database of every death in New Jersey. The Glaister Equation with a cooling rate of 2 degrees/hour was the method I found to be the most accurate. Additionally, I show that it is feasible to create an equation that provides a more reliable time of death estimation for this data set [1].

Literature Review

The best approach for determining the time of death using temperature monitoring is still Henssge's nomogram [2]. A way to calculate PMI using temperature is Henssge's nomogram, although unlike the Glaister Equation, it also takes into account a few other crucial variables. The body temperature, surrounding temperature, body weight, clothes, and whether the body was submerged in air or water must all be taken into account while using this nomogram. There are two nomograms: one for environments with temperatures up to 23°C and the other for environments with temperatures above 23°C [3]. The postmortem plateau results in two distinct nomograms. The postmortem plateau is a line that aims to depict how a human corpse cools, which then provides an estimate of how long it has been since someone died. In warmer weather, above 23 degrees Celsius, the postmortem plateau is shorter, whereas in colder weather, below 23 degrees Celsius, it is longer.

Discussion

Given that the decedent's weight is known, it can be seen as bold numbers in tens either along the bottom right side of the nomogram, inside the ambient temperature, or on the left side, inside the body temperature. The weight must be rounded to the closest 10 if the precise body weight is not visible. However, the body weight may first be adjusted with a corrective factor. The corrective factor must be multiplied by the original body weight because the chart depicts several conditions a decedent might be in, including various clothing situations. The nomogram will be searched for that particular number. Once it joins the third line, the curving line that follows the new estimated body weight number must be followed. The time since the deceased person's death will be calculated using that number [4].

Finding the time of death is difficult, thus it has been studied for hundreds of years. The precise moment of physiological death cannot be determined by a single factor. It is always a ballpark figure. Yet, the Medical Examiner may frequently determine the physiologic time of death with some degree of accuracy when the concepts are properly applied. There are numerous variables that affect when someone passes away, making it nearly impossible to provide a single solution that would apply to every decedent's body, regardless of the influencing external variables. To get as near to the actual time of death as feasible, equations might be tried to be determined [5,6].

Conclusion

These techniques were discovered to be ineffective and to produce inconsistently inaccurate outcomes. Several research have discovered comparable findings of these approaches' imprecision in the past, supporting my analysis. In a review of the Henssge nomogram method employing 84 human cases, the method exaggerated PMI for bodies with high mass or large surface area and that 57.1% of cases did not fall within the 95% confidence interval. Out of the three approaches, I discovered that the Glaister Equation with 2 deg/hr as the denominator produced the best results, though they were still not the best.

Acknowledgment

None.

Conflicts of Interest

None.

References

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