Temperature-based death time estimation in near equilibrium: Asymptotic confidence interval estimation.

Temperature based death time estimation (TDE) is severely limited in situations where body core temperature has almost decreased to ambient temperature. The TDE method of Marshall/Hoare and Henßge (MHH) defines a lower bound TK for body core temperature below which the time p.m. should be stated to be >10h only. A recent study (Potente et al., 2017 [10]) established a new method, called variance-bias-tradeoff (VBT) complementing MHH in constructing a right-side-half-infinite 97.5%-confidence interval for such 'near equilibrium'-situations. It seemingly proved the validity for all body core temperatures T<TK. The present study investigates VBT further and discovers that VBT-applicability has an upper limit in time since death. We show how to compute this upper limit explicitly in forensic casework and explain by the frequentist confidence interval probability interpretation why the former study (Potente et al., 2017 [10]) missed this upper limit.

[1]  T Ishikawa,et al.  Minimum time since death when the body has either reached or closely approximated equilibrium with ambient temperature. , 2017, Forensic science international.

[2]  Guy N. Rutty,et al.  The estimation of the time since death using temperatures recorded from the external auditory canal , 2005, Forensic science, medicine, and pathology.

[3]  C Henssge,et al.  Death time estimation in case work. I. The rectal temperature time of death nomogram. , 1988, Forensic science international.

[4]  C. Cattaneo,et al.  Cooling Rates of the Ear and Brain in Pig Heads Submerged in Water: Implications for Postmortem Interval Estimation of Cadavers Found in Still Water , 2007, The American journal of forensic medicine and pathology.

[5]  Z. Jankowski,et al.  The Potential Use of the Eye Temperature Decrease in Determining the Time of Death in the Early Postmortem Period: Studies in Pigs , 2010, The American journal of forensic medicine and pathology.

[6]  R. Kaliszan,et al.  Verification of the exponential model of body temperature decrease after death in pigs , 2005, Experimental physiology.

[7]  M. Kaliszan.  First practical applications of eye temperature measurements for estimation of the time of death in casework. Report of three cases. , 2012, Forensic science international.

[8]  C. Henßge.  Todeszeitschätzungen durch die mathematische Beschreibung der rektalen Leichenabkühlung unter verschiedenen Abkühlungsbedingungen , 2004, Zeitschrift für Rechtsmedizin.

[9]  Jimmy L. Smart,et al.  Use of a Finite Element Model of Heat Transport in the Human Eye to Predict Time of Death , 2013, Journal of forensic sciences.

[10]  B. Brinkmann,et al.  Todeszeitbestimmung durch Messung der zentralen Hirntemperatur , 1984, Zeitschrift für Rechtsmedizin.

[11]  G. Rutty.  The estimation of the time since death using temperatures recorded from the external auditory canal , 2005, Forensic science, medicine, and pathology.

[12]  M. Kaliszan.  Studies on time of death estimation in the early post mortem period -- application of a method based on eyeball temperature measurement to human bodies. , 2013, Legal Medicine.

[13]  L. Nokes,et al.  The use of either the nose or outer ear as a means of determining the postmortem period of a human corpse. , 1992, Forensic science international.

[14]  P. Guilloteau,et al.  Outer ear temperature and time of death. , 1996, Forensic science international.

[15]  M. Fisz.  Wahrscheinlichkeitsrechnung und mathematische Statistik , 1962 .