Postmortem interval estimation from body temperature data only.

One of the most consistently used methods of postmortem interval estimation (PMIE) is by means of body temperature measurements. Several variations of this method exist, from simple 'rules of the thumb' to quite complex equations requiring a knowledge of body mass and height. All of these methods employ a certain degree of approximation and perhaps the use of standard values and tables, and all of them are susceptible to some degree of error. The present study, at the Department of Forensic Medicine, Leeds, was initiated by the Home Office to investigate the extent of the errors which might be encountered in the use of these methods, and to devise a more simple and accurate method. The method devised is called the time-dependent-z equation, for purely theoretical reasons. It will be referred to as the TDZE method. The TDZE method requires the measurement of two rectal temperatures, about 1 h apart, a little mental arithmetic and reference to a single standard curve. The method is valid for all bodies, obese or emaciated, clothed or naked, in all environmental conditions, without modification. Results of the use of the method on data collected from 67 coroner's cases compare favourably with the results obtained by the use of other methods on the same data.