The method of Al-Alousi and Anderson to estimate the time of death uses organ and environmental temperature to calculate a temperature difference ratio which is then compared to a cooling curve. The method uses different cooling curves depending on whether the body is clothed or naked.
Organ temperature to measure:
(1) rectum
(2) liver
(3) brain
(4) any organ for which a cooling curve is available
temperature difference ratio =
= ((organ temperature in °C at time 1) - (environmental temperature in °C at time 1)) / ((organ temperature in °C at time of death) - (environmental temperature in °C at time 1))
Liver, Body Naked
For temperature difference ratio >=0.23
mean time since death in hours at time 1 =
= (-39.477 * ((temperature difference ratio)^3)) + (104.578 * ((temperature difference ratio)^2)) - (103.96 * (temperature difference ratio)) + 38.859
For temperature difference ratio >=0.06
mean time since death in hours at time 1 =
= (863.727 * ((temperature difference ratio)^2)) - (405.879 * (temperature difference ratio)) + 67.726
For ratio < 0.06, time of death is assumed to be > 50 hours.
Liver, Body Covered
For temperature difference ratio >=0.5
mean time since death in hours at time 1 =
= (-40 * (temperature difference ratio)) + 40
For temperature difference ratio >=0.17
mean time since death in hours at time 1 =
= (163.487 * ((temperature difference ratio)^2)) - (191.52* (temperature difference ratio)) + 75.143
For ratio < 0.17, time of death is assumed to be > 50 hours.
Rectum, Body Naked
For temperature difference ratio >=0.22
mean time since death in hours at time 1 =
= (29.677 * ((temperature difference ratio)^2)) - (61.847 * (temperature difference ratio))+32.17
For temperature difference ratio >=0.01
mean time since death in hours at time 1 =
= (320.2587 * ((temperature difference ratio)^2)) - (205.8496 * (temperature difference ratio)) + 49.8496
For ratio < 0.01, time of death is assumed to be > 50 hours.
Rectum, Body Covered
For temperature difference ratio >=0.33
mean time since death in hours at time 1 =
= (27.4789 * ((temperature difference ratio)^2))-(66.3977 * (temperature difference ratio)) + 38.91878
For temperature difference ratio >=0.01
mean time since death in hours at time 1 =
= (211.783 * ((temperature difference ratio)^2)) - (159.305 * (temperature difference ratio)) + 49.59259
For ratio < 0.01, time of death is assumed to be > 50 hours.
Limitations:
• The body temperature at the time of death may not be 37 °C.
• If the environmental temperature varies widely and is not constant, then the environmental temperature used may be misleading.
• Above 40-50 hours the curves flatten and may not be accurate.
• The cooling curves show a hatched area +/- 1 standard deviation, so that the estimates are only rough time indicators.
